166165507 has 4 divisors (see below), whose sum is σ = 174911080. Its totient is φ = 157419936.

The previous prime is 166165481. The next prime is 166165523. The reversal of 166165507 is 705561661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 166165507 - 2⁷ = 166165379 is a prime.

It is a super-2 number, since 2×166165507² = 55221951433134098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166165567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4372758 + ... + 4372795.

It is an arithmetic number, because the mean of its divisors is an integer number (43727770).

Almost surely, 2^166165507 is an apocalyptic number.

166165507 is a deficient number, since it is larger than the sum of its proper divisors (8745573).

166165507 is an equidigital number, since it uses as much as digits as its factorization.

166165507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8745572.

The product of its (nonzero) digits is 37800, while the sum is 37.

The square root of 166165507 is about 12890.5200438151. The cubic root of 166165507 is about 549.7690567603.

The spelling of 166165507 in words is "one hundred sixty-six million, one hundred sixty-five thousand, five hundred seven".