216866560 has 36 divisors (see below), whose sum is σ = 519466248. Its totient is φ = 86746112.

The previous prime is 216866537. The next prime is 216866561. The reversal of 216866560 is 65668612.

It is a super-2 number, since 2×216866560² = 94062209692467200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216866561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 83434 + ... + 85993.

It is an arithmetic number, because the mean of its divisors is an integer number (14429618).

Almost surely, 2^216866560 is an apocalyptic number.

216866560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216866560 is an abundant number, since it is smaller than the sum of its proper divisors (302599688).

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

216866560 is an equidigital number, since it uses as much as digits as its factorization.

216866560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169448 (or 169434 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 40.

The square root of 216866560 is about 14726.3899174238. The cubic root of 216866560 is about 600.8012997585.

The spelling of 216866560 in words is "two hundred sixteen million, eight hundred sixty-six thousand, five hundred sixty".