216456904 has 8 divisors (see below), whose sum is σ = 405856710. Its totient is φ = 108228448.

The previous prime is 216456901. The next prime is 216456913. The reversal of 216456904 is 409654612.

It can be written as a sum of positive squares in only one way, i.e., 139192804 + 77264100 = 11798^2 + 8790^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (216456901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13528549 + ... + 13528564.

Almost surely, 2^216456904 is an apocalyptic number.

It is an amenable number.

216456904 is a deficient number, since it is larger than the sum of its proper divisors (189399806).

216456904 is a wasteful number, since it uses less digits than its factorization.

216456904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27057119 (or 27057115 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 37.

The square root of 216456904 is about 14712.4744349820. The cubic root of 216456904 is about 600.4227613108.

The spelling of 216456904 in words is "two hundred sixteen million, four hundred fifty-six thousand, nine hundred four".