216985290 has 32 divisors (see below), whose sum is σ = 522187776. Its totient is φ = 57704640.

The previous prime is 216985283. The next prime is 216985309. The reversal of 216985290 is 92589612.

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1495 + ... + 20885.

It is an arithmetic number, because the mean of its divisors is an integer number (16318368).

Almost surely, 2^216985290 is an apocalyptic number.

216985290 is an abundant number, since it is smaller than the sum of its proper divisors (305202486).

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

216985290 is a wasteful number, since it uses less digits than its factorization.

216985290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19774.

The product of its (nonzero) digits is 77760, while the sum is 42.

The square root of 216985290 is about 14730.4205642609. The cubic root of 216985290 is about 600.9109218912.

The spelling of 216985290 in words is "two hundred sixteen million, nine hundred eighty-five thousand, two hundred ninety".