216585988 has 12 divisors (see below), whose sum is σ = 379143772. Its totient is φ = 108259200.

The previous prime is 216585983. The next prime is 216585989. The reversal of 216585988 is 889585612.

It can be written as a sum of positive squares in 2 ways, for example, as 95101504 + 121484484 = 9752^2 + 11022^2 .

It is a super-2 number, since 2×216585988² = 93818980395872288, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (216585983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10888 + ... + 23488.

Almost surely, 2^216585988 is an apocalyptic number.

It is an amenable number.

216585988 is a deficient number, since it is larger than the sum of its proper divisors (162557784).

216585988 is a wasteful number, since it uses less digits than its factorization.

216585988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16902 (or 16900 counting only the distinct ones).

The product of its digits is 1382400, while the sum is 52.

The square root of 216585988 is about 14716.8606706729. The cubic root of 216585988 is about 600.5420915619.

The spelling of 216585988 in words is "two hundred sixteen million, five hundred eighty-five thousand, nine hundred eighty-eight".