166420426621187 has 2 divisors, whose sum is σ = 166420426621188. Its totient is φ = 166420426621186.

The previous prime is 166420426621177. The next prime is 166420426621231. The reversal of 166420426621187 is 781126624024661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 166420426621187 - 2²² = 166420422426883 is a prime.

It is not a weakly prime, because it can be changed into another prime (166420426621147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83210213310593 + 83210213310594.

It is an arithmetic number, because the mean of its divisors is an integer number (83210213310594).

Almost surely, 2^{166420426621187} is an apocalyptic number.

166420426621187 is a deficient number, since it is larger than the sum of its proper divisors (1).

166420426621187 is an equidigital number, since it uses as much as digits as its factorization.

166420426621187 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9289728, while the sum is 56.

The spelling of 166420426621187 in words is "one hundred sixty-six trillion, four hundred twenty billion, four hundred twenty-six million, six hundred twenty-one thousand, one hundred eighty-seven".