21513310232431 has 8 divisors (see below), whose sum is σ = 21786948529920. Its totient is φ = 21239704882968.

The previous prime is 21513310232413. The next prime is 21513310232443. The reversal of 21513310232431 is 13423201331512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21513310232431 - 2²⁵ = 21513276677999 is a prime.

It is a super-2 number, since 2×21513310232431² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21513310232393 and 21513310232402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21513310272431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6921481 + ... + 9535906.

It is an arithmetic number, because the mean of its divisors is an integer number (2723368566240).

Almost surely, 2^{21513310232431} is an apocalyptic number.

21513310232431 is a deficient number, since it is larger than the sum of its proper divisors (273638297489).

21513310232431 is a wasteful number, since it uses less digits than its factorization.

21513310232431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16474013.

The product of its (nonzero) digits is 12960, while the sum is 31.

Adding to 21513310232431 its reverse (13423201331512), we get a palindrome (34936511563943).

The spelling of 21513310232431 in words is "twenty-one trillion, five hundred thirteen billion, three hundred ten million, two hundred thirty-two thousand, four hundred thirty-one".