165664026 has 48 divisors (see below), whose sum is σ = 401139648. Its totient is φ = 48974400.

The previous prime is 165664019. The next prime is 165664039. The reversal of 165664026 is 620466561.

It is a happy number.

165664026 is a `hidden beast` number, since 1 + 6 + 5 + 6 + 640 + 2 + 6 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2086 + ... + 18321.

It is an arithmetic number, because the mean of its divisors is an integer number (8357076).

Almost surely, 2^165664026 is an apocalyptic number.

165664026 is an abundant number, since it is smaller than the sum of its proper divisors (235475622).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165664026 is a wasteful number, since it uses less digits than its factorization.

165664026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20467 (or 20464 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 165664026 is about 12871.0538030108. The cubic root of 165664026 is about 549.2154389515.

The spelling of 165664026 in words is "one hundred sixty-five million, six hundred sixty-four thousand, twenty-six".