166645831815 has 32 divisors (see below), whose sum is σ = 296713103040. Its totient is φ = 88741623168.

The previous prime is 166645831801. The next prime is 166645831817. The reversal of 166645831815 is 518138546661.

It is not a de Polignac number, because 166645831815 - 2⁴ = 166645831799 is a prime.

It is a super-2 number, since 2×166645831815² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166645831817) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 857032 + ... + 1033341.

It is an arithmetic number, because the mean of its divisors is an integer number (9272284470).

Almost surely, 2^166645831815 is an apocalyptic number.

166645831815 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

166645831815 is a deficient number, since it is larger than the sum of its proper divisors (130067271225).

166645831815 is a wasteful number, since it uses less digits than its factorization.

166645831815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1891040 (or 1891034 counting only the distinct ones).

The product of its digits is 4147200, while the sum is 54.

The spelling of 166645831815 in words is "one hundred sixty-six billion, six hundred forty-five million, eight hundred thirty-one thousand, eight hundred fifteen".