21210232131 has 32 divisors (see below), whose sum is σ = 34291084800. Its totient is φ = 12850215840.

The previous prime is 21210232123. The next prime is 21210232151. The reversal of 21210232131 is 13123201212.

21210232131 is a `hidden beast` number, since 212 + 102 + 321 + 31 = 666.

It is not a de Polignac number, because 21210232131 - 2³ = 21210232123 is a prime.

It is a super-2 number, since 2×21210232131² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21210232151) 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 31 ways as a sum of consecutive naturals, for example, 974985 + ... + 996501.

It is an arithmetic number, because the mean of its divisors is an integer number (1071596400).

Almost surely, 2^21210232131 is an apocalyptic number.

21210232131 is a deficient number, since it is larger than the sum of its proper divisors (13080852669).

21210232131 is a wasteful number, since it uses less digits than its factorization.

21210232131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24856 (or 24850 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21210232131 its reverse (13123201212), we get a palindrome (34333433343).

The spelling of 21210232131 in words is "twenty-one billion, two hundred ten million, two hundred thirty-two thousand, one hundred thirty-one".