Highly Cototient Number - Primes

Primes

The first few highly cototient numbers which are primes (sequence A105440 in OEIS) are

2, 23, 47, 59, 83, 89, 113, 167, 269, 389, 419, 509, 659, 839.
Totient function
  • Euler's totient function
  • Jordan's totient function
  • Nontotient
  • Noncototient
  • Highly totient number
  • Sparsely totient number
  • Highly cototient number
Prime number classes
By formula
  • Fermat (22n + 1)
  • Mersenne (2p − 1)
  • Double Mersenne (22p−1 − 1)
  • Wagstaff (2p + 1)/3
  • Proth (k·2n + 1)
  • Factorial (n! ± 1)
  • Primorial (pn# ± 1)
  • Euclid (pn# + 1)
  • Pythagorean (4n + 1)
  • Pierpont (2u·3v + 1)
  • Solinas (2a ± 2b ± 1)
  • Cullen (n·2n + 1)
  • Woodall (n·2n − 1)
  • Cuban (x3 − y3)/(xy)
  • Carol (2n − 1)2 − 2
  • Kynea (2n + 1)2 − 2
  • Leyland (xy + yx)
  • Thabit (3·2n − 1)
  • Mills (floor(A3n))
By integer sequence
  • Fibonacci
  • Lucas
  • Motzkin
  • Bell
  • Partitions
  • Pell
  • Perrin
  • Newman–Shanks–Williams
By property
  • Lucky
  • Wall–Sun–Sun
  • Wilson
  • Wieferich
  • Wieferich pair
  • Fortunate
  • Ramanujan
  • Pillai
  • Regular
  • Strong
  • Stern
  • Supersingular (elliptic curve)
  • Supersingular (moonshine theory)
  • Wolstenholme
  • Good
  • Super
  • Higgs
  • Highly cototient
  • Illegal
Base-dependent
  • Happy
  • Dihedral
  • Palindromic
  • Emirp
  • Repunit (10n − 1)/9
  • Permutable
  • Circular
  • Strobogrammatic
  • Minimal
  • Full reptend
  • Unique
  • Primeval
  • Self
  • Smarandache–Wellin
Patterns
  • Twin (p, p + 2)
  • Triplet (p, p + 2 or p + 4, p + 6)
  • Quadruplet (p, p + 2, p + 6, p + 8)
  • Tuple
  • Cousin (p, p + 4)
  • Sexy (p, p + 6)
  • Chen
  • Sophie Germain (p, 2p + 1)
  • Cunningham chain (p, 2p ± 1, …)
  • Safe (p, (p − 1)/2)
  • Arithmetic progression (p + a·n, n = 0, 1, …)
  • Balanced (consecutive pn, p, p + n)
By size
  • Titanic
  • Gigantic
  • Mega
  • Largest known
Complex numbers
  • Eisenstein prime
  • Gaussian prime
Composite numbers
  • Pseudoprime
  • Almost prime
  • Semiprime
  • Interprime
Related topics
  • Probable prime
  • Industrial-grade prime
  • Formula for primes
  • Prime gap
List of prime numbers

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