216520580 has 36 divisors (see below), whose sum is σ = 479899980. Its totient is φ = 82047168.

The previous prime is 216520573. The next prime is 216520607. The reversal of 216520580 is 85025612.

It can be written as a sum of positive squares in 2 ways, for example, as 136095556 + 80425024 = 11666^2 + 8968^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7775 + ... + 22214.

It is an arithmetic number, because the mean of its divisors is an integer number (13330555).

Almost surely, 2^216520580 is an apocalyptic number.

216520580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216520580 is an abundant number, since it is smaller than the sum of its proper divisors (263379400).

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

216520580 is a wasteful number, since it uses less digits than its factorization.

216520580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30036 (or 30015 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 29.

The square root of 216520580 is about 14714.6382898120. The cubic root of 216520580 is about 600.4816317998.

The spelling of 216520580 in words is "two hundred sixteen million, five hundred twenty thousand, five hundred eighty".