166638715 has 16 divisors (see below), whose sum is σ = 206415360. Its totient is φ = 129080160.

The previous prime is 166638707. The next prime is 166638739. The reversal of 166638715 is 517836661.

It is not a de Polignac number, because 166638715 - 2³ = 166638707 is a prime.

It is a super-2 number, since 2×166638715² = 55536922673702450, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15550 + ... + 23980.

It is an arithmetic number, because the mean of its divisors is an integer number (12900960).

Almost surely, 2^166638715 is an apocalyptic number.

166638715 is a deficient number, since it is larger than the sum of its proper divisors (39776645).

166638715 is an equidigital number, since it uses as much as digits as its factorization.

166638715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8562.

The product of its digits is 181440, while the sum is 43.

The square root of 166638715 is about 12908.8618785701. The cubic root of 166638715 is about 550.2904416392.

The spelling of 166638715 in words is "one hundred sixty-six million, six hundred thirty-eight thousand, seven hundred fifteen".