216985280 has 56 divisors (see below), whose sum is σ = 547103808. Its totient is φ = 81686528.

The previous prime is 216985261. The next prime is 216985283. The reversal of 216985280 is 82589612.

It is a super-2 number, since 2×216985280² = 94165223473356800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (216985283) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14504 + ... + 25383.

Almost surely, 2^216985280 is an apocalyptic number.

216985280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216985280 is an abundant number, since it is smaller than the sum of its proper divisors (330118528).

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

216985280 is a wasteful number, since it uses less digits than its factorization.

216985280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39921 (or 39911 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 41.

The square root of 216985280 is about 14730.4202248273. The cubic root of 216985280 is about 600.9109126600.

The spelling of 216985280 in words is "two hundred sixteen million, nine hundred eighty-five thousand, two hundred eighty".