216131565 has 24 divisors (see below), whose sum is σ = 374461920. Its totient is φ = 106401984.

The previous prime is 216131563. The next prime is 216131569. The reversal of 216131565 is 565131612.

It is not a de Polignac number, because 216131565 - 2¹ = 216131563 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216131561) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40095 + ... + 45164.

It is an arithmetic number, because the mean of its divisors is an integer number (15602580).

Almost surely, 2^216131565 is an apocalyptic number.

It is an amenable number.

216131565 is a deficient number, since it is larger than the sum of its proper divisors (158330355).

216131565 is a wasteful number, since it uses less digits than its factorization.

216131565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85293 (or 85280 counting only the distinct ones).

The product of its digits is 5400, while the sum is 30.

The square root of 216131565 is about 14701.4137075317. The cubic root of 216131565 is about 600.1217947195.

The spelling of 216131565 in words is "two hundred sixteen million, one hundred thirty-one thousand, five hundred sixty-five".