216581672 has 16 divisors (see below), whose sum is σ = 406492800. Its totient is φ = 108183600.

The previous prime is 216581671. The next prime is 216581681. The reversal of 216581672 is 276185612.

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (216581671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4472 + ... + 21287.

It is an arithmetic number, because the mean of its divisors is an integer number (25405800).

Almost surely, 2^216581672 is an apocalyptic number.

It is an amenable number.

216581672 is a deficient number, since it is larger than the sum of its proper divisors (189911128).

216581672 is a wasteful number, since it uses less digits than its factorization.

216581672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26816 (or 26812 counting only the distinct ones).

The product of its digits is 40320, while the sum is 38.

The square root of 216581672 is about 14716.7140354089. The cubic root of 216581672 is about 600.5381024505.

The spelling of 216581672 in words is "two hundred sixteen million, five hundred eighty-one thousand, six hundred seventy-two".