216628564 has 12 divisors (see below), whose sum is σ = 379206324. Its totient is φ = 108283904.

The previous prime is 216628553. The next prime is 216628591. The reversal of 216628564 is 465826612.

It can be written as a sum of positive squares in 2 ways, for example, as 178436164 + 38192400 = 13358^2 + 6180^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18132 + ... + 27604.

It is an arithmetic number, because the mean of its divisors is an integer number (31600527).

Almost surely, 2^216628564 is an apocalyptic number.

It is an amenable number.

216628564 is a deficient number, since it is larger than the sum of its proper divisors (162577760).

216628564 is a wasteful number, since it uses less digits than its factorization.

216628564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15194 (or 15192 counting only the distinct ones).

The product of its digits is 138240, while the sum is 40.

The square root of 216628564 is about 14718.3071037399. The cubic root of 216628564 is about 600.5814400674.

The spelling of 216628564 in words is "two hundred sixteen million, six hundred twenty-eight thousand, five hundred sixty-four".