216629664 has 24 divisors (see below), whose sum is σ = 568653120. Its totient is φ = 72209856.

The previous prime is 216629639. The next prime is 216629687. The reversal of 216629664 is 466926612.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×216629664² = 93856822649505792, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1128184 + ... + 1128375.

It is an arithmetic number, because the mean of its divisors is an integer number (23693880).

Almost surely, 2^216629664 is an apocalyptic number.

216629664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

216629664 is an abundant number, since it is smaller than the sum of its proper divisors (352023456).

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

216629664 is a wasteful number, since it uses less digits than its factorization.

216629664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2256572 (or 2256564 counting only the distinct ones).

The product of its digits is 186624, while the sum is 42.

The square root of 216629664 is about 14718.3444721205. The cubic root of 216629664 is about 600.5824566131.

The spelling of 216629664 in words is "two hundred sixteen million, six hundred twenty-nine thousand, six hundred sixty-four".