216591488 has 128 divisors (see below), whose sum is σ = 488376000. Its totient is φ = 95219712.

The previous prime is 216591467. The next prime is 216591493. The reversal of 216591488 is 884195612.

It is a tau number, because it is divible by the number of its divisors (128).

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2609495 + ... + 2609577.

Almost surely, 2^216591488 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 216591488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (244188000).

216591488 is an abundant number, since it is smaller than the sum of its proper divisors (271784512).

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

216591488 is a wasteful number, since it uses less digits than its factorization.

216591488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182 (or 170 counting only the distinct ones).

The product of its digits is 138240, while the sum is 44.

The square root of 216591488 is about 14717.0475299905. The cubic root of 216591488 is about 600.5471749217.

The spelling of 216591488 in words is "two hundred sixteen million, five hundred ninety-one thousand, four hundred eighty-eight".