21103231131 has 32 divisors (see below), whose sum is σ = 32020285440. Its totient is φ = 13729111200.

The previous prime is 21103231081. The next prime is 21103231159. The reversal of 21103231131 is 13113230112.

21103231131 is a `hidden beast` number, since 211 + 0 + 323 + 1 + 131 = 666.

It is not a de Polignac number, because 21103231131 - 2¹¹ = 21103229083 is a prime.

It is a super-2 number, since 2×21103231131² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21103231181) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1363446 + ... + 1378836.

It is an arithmetic number, because the mean of its divisors is an integer number (1000633920).

Almost surely, 2^21103231131 is an apocalyptic number.

21103231131 is a deficient number, since it is larger than the sum of its proper divisors (10917054309).

21103231131 is a wasteful number, since it uses less digits than its factorization.

21103231131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16624 (or 16618 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 21103231131 its reverse (13113230112), we get a palindrome (34216461243).

The spelling of 21103231131 in words is "twenty-one billion, one hundred three million, two hundred thirty-one thousand, one hundred thirty-one".