215983664 has 20 divisors (see below), whose sum is σ = 450658656. Its totient is φ = 99684672.

The previous prime is 215983643. The next prime is 215983681. The reversal of 215983664 is 466389512.

It is a super-2 number, since 2×215983664² = 93297886229729792, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 518984 + ... + 519399.

Almost surely, 2^215983664 is an apocalyptic number.

It is an amenable number.

215983664 is an abundant number, since it is smaller than the sum of its proper divisors (234674992).

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

215983664 is a wasteful number, since it uses less digits than its factorization.

215983664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1038404 (or 1038398 counting only the distinct ones).

The product of its digits is 311040, while the sum is 44.

The square root of 215983664 is about 14696.3826841846. The cubic root of 215983664 is about 599.9848736927.

The spelling of 215983664 in words is "two hundred fifteen million, nine hundred eighty-three thousand, six hundred sixty-four".