213112531 has 4 divisors (see below), whose sum is σ = 224329000. Its totient is φ = 201896064.

The previous prime is 213112519. The next prime is 213112553. The reversal of 213112531 is 135211312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 213112531 - 2⁵ = 213112499 is a prime.

It is a super-2 number, since 2×213112531² = 90833901738451922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 11216449 = 213112531 / (2 + 1 + 3 + 1 + 1 + 2 + 5 + 3 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 213112499 and 213112508.

It is not an unprimeable number, because it can be changed into a prime (213112511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5608206 + ... + 5608243.

It is an arithmetic number, because the mean of its divisors is an integer number (56082250).

Almost surely, 2^213112531 is an apocalyptic number.

213112531 is a deficient number, since it is larger than the sum of its proper divisors (11216469).

213112531 is a wasteful number, since it uses less digits than its factorization.

213112531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11216468.

The product of its digits is 180, while the sum is 19.

The square root of 213112531 is about 14598.3742588002. The cubic root of 213112531 is about 597.3144149152.

Adding to 213112531 its reverse (135211312), we get a palindrome (348323843).

The spelling of 213112531 in words is "two hundred thirteen million, one hundred twelve thousand, five hundred thirty-one".