166655491 has 2 divisors, whose sum is σ = 166655492. Its totient is φ = 166655490.

The previous prime is 166655443. The next prime is 166655501. The reversal of 166655491 is 194556661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 166655491 - 2²⁷ = 32437763 is a prime.

It is not a weakly prime, because it can be changed into another prime (166655191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83327745 + 83327746.

It is an arithmetic number, because the mean of its divisors is an integer number (83327746).

Almost surely, 2^166655491 is an apocalyptic number.

166655491 is a deficient number, since it is larger than the sum of its proper divisors (1).

166655491 is an equidigital number, since it uses as much as digits as its factorization.

166655491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 194400, while the sum is 43.

The square root of 166655491 is about 12909.5116483932. The cubic root of 166655491 is about 550.3089074614.

The spelling of 166655491 in words is "one hundred sixty-six million, six hundred fifty-five thousand, four hundred ninety-one".