166601917 has 2 divisors, whose sum is σ = 166601918. Its totient is φ = 166601916.

The previous prime is 166601893. The next prime is 166601933. The reversal of 166601917 is 719106661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 113763556 + 52838361 = 10666^2 + 7269^2 .

It is a cyclic number.

It is not a de Polignac number, because 166601917 - 2¹¹ = 166599869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166601117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83300958 + 83300959.

It is an arithmetic number, because the mean of its divisors is an integer number (83300959).

Almost surely, 2^166601917 is an apocalyptic number.

It is an amenable number.

166601917 is a deficient number, since it is larger than the sum of its proper divisors (1).

166601917 is an equidigital number, since it uses as much as digits as its factorization.

166601917 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13608, while the sum is 37.

The square root of 166601917 is about 12907.4364999406. The cubic root of 166601917 is about 550.2499326886.

The spelling of 166601917 in words is "one hundred sixty-six million, six hundred one thousand, nine hundred seventeen".