21131430524 has 6 divisors (see below), whose sum is σ = 36980003424. Its totient is φ = 10565715260.

The previous prime is 21131430521. The next prime is 21131430553. The reversal of 21131430524 is 42503413112.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21131430493 and 21131430502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21131430521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2641428812 + ... + 2641428819.

It is an arithmetic number, because the mean of its divisors is an integer number (6163333904).

Almost surely, 2^21131430524 is an apocalyptic number.

It is an amenable number.

21131430524 is a deficient number, since it is larger than the sum of its proper divisors (15848572900).

21131430524 is a wasteful number, since it uses less digits than its factorization.

21131430524 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5282857635 (or 5282857633 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

Adding to 21131430524 its reverse (42503413112), we get a palindrome (63634843636).

The spelling of 21131430524 in words is "twenty-one billion, one hundred thirty-one million, four hundred thirty thousand, five hundred twenty-four".