215113131 has 16 divisors (see below), whose sum is σ = 321784320. Its totient is φ = 142014600.

The previous prime is 215113127. The next prime is 215113163. The reversal of 215113131 is 131311512.

215113131 is a `hidden beast` number, since 21 + 511 + 3 + 131 = 666.

It is not a de Polignac number, because 215113131 - 2² = 215113127 is a prime.

It is a super-2 number, since 2×215113131² = 92547318257246322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (215113531) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35895 + ... + 41456.

It is an arithmetic number, because the mean of its divisors is an integer number (20111520).

Almost surely, 2^215113131 is an apocalyptic number.

215113131 is a deficient number, since it is larger than the sum of its proper divisors (106671189).

215113131 is a wasteful number, since it uses less digits than its factorization.

215113131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77463 (or 77457 counting only the distinct ones).

The product of its digits is 90, while the sum is 18.

The square root of 215113131 is about 14666.7355263535. The cubic root of 215113131 is about 599.1776985487.

Adding to 215113131 its reverse (131311512), we get a palindrome (346424643).

It can be divided in two parts, 21511 and 3131, that added together give a palindrome (24642).

The spelling of 215113131 in words is "two hundred fifteen million, one hundred thirteen thousand, one hundred thirty-one".