21307463031 has 4 divisors (see below), whose sum is σ = 28409950712. Its totient is φ = 14204975352.

The previous prime is 21307463017. The next prime is 21307463063. The reversal of 21307463031 is 13036470312.

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

It is not a de Polignac number, because 21307463031 - 2¹¹ = 21307460983 is a prime.

It is a super-2 number, since 2×21307463031² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21307463031.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21307463131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3551243836 + ... + 3551243841.

It is an arithmetic number, because the mean of its divisors is an integer number (7102487678).

Almost surely, 2^21307463031 is an apocalyptic number.

21307463031 is a deficient number, since it is larger than the sum of its proper divisors (7102487681).

21307463031 is an equidigital number, since it uses as much as digits as its factorization.

21307463031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7102487680.

The product of its (nonzero) digits is 9072, while the sum is 30.

The spelling of 21307463031 in words is "twenty-one billion, three hundred seven million, four hundred sixty-three thousand, thirty-one".