216620964 has 144 divisors (see below), whose sum is σ = 652579200. Its totient is φ = 60540480.

The previous prime is 216620951. The next prime is 216621001. The reversal of 216620964 is 469026612.

216620964 is a `hidden beast` number, since 21 + 6 + 620 + 9 + 6 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 654279 + ... + 654609.

It is an arithmetic number, because the mean of its divisors is an integer number (4531800).

Almost surely, 2^216620964 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216620964, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (326289600).

216620964 is an abundant number, since it is smaller than the sum of its proper divisors (435958236).

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

216620964 is a wasteful number, since it uses less digits than its factorization.

216620964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 415 (or 396 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 216620964 is about 14718.0489196089. The cubic root of 216620964 is about 600.5744165672.

The spelling of 216620964 in words is "two hundred sixteen million, six hundred twenty thousand, nine hundred sixty-four".