215664564 has 24 divisors (see below), whose sum is σ = 516818848. Its totient is φ = 69945120.

The previous prime is 215664539. The next prime is 215664607. The reversal of 215664564 is 465466512.

It is a super-2 number, since 2×215664564² = 93022408330620192, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 242422 + ... + 243309.

Almost surely, 2^215664564 is an apocalyptic number.

It is an amenable number.

215664564 is an abundant number, since it is smaller than the sum of its proper divisors (301154284).

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

215664564 is a wasteful number, since it uses less digits than its factorization.

215664564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485775 (or 485773 counting only the distinct ones).

The product of its digits is 172800, while the sum is 39.

The square root of 215664564 is about 14685.5222583332. The cubic root of 215664564 is about 599.6892501965.

The spelling of 215664564 in words is "two hundred fifteen million, six hundred sixty-four thousand, five hundred sixty-four".