216565290 has 48 divisors (see below), whose sum is σ = 563821128. Its totient is φ = 57673728.

The previous prime is 216565289. The next prime is 216565333. The reversal of 216565290 is 92565612.

216565290 is a `hidden beast` number, since 2 + 1 + 6 + 565 + 2 + 90 = 666.

216565290 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 201611601 + 14953689 = 14199^2 + 3867^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 106362 + ... + 108378.

Almost surely, 2^216565290 is an apocalyptic number.

216565290 is an abundant number, since it is smaller than the sum of its proper divisors (347255838).

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

216565290 is a wasteful number, since it uses less digits than its factorization.

216565290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3223 (or 3220 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 216565290 is about 14716.1574468337. The cubic root of 216565290 is about 600.5229607210.

The spelling of 216565290 in words is "two hundred sixteen million, five hundred sixty-five thousand, two hundred ninety".