21200013031 has 6 divisors (see below), whose sum is σ = 22161828920. Its totient is φ = 20278272828.

The previous prime is 21200012959. The next prime is 21200013053. The reversal of 21200013031 is 13031000212.

It is not a de Polignac number, because 21200013031 - 2⁷ = 21200012903 is a prime.

It is a super-2 number, since 2×21200013031² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200713031) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 20037291 + ... + 20038348.

Almost surely, 2^21200013031 is an apocalyptic number.

21200013031 is a deficient number, since it is larger than the sum of its proper divisors (961815889).

21200013031 is an equidigital number, since it uses as much as digits as its factorization.

21200013031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40075685 (or 40075662 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21200013031 its reverse (13031000212), we get a palindrome (34231013243).

The spelling of 21200013031 in words is "twenty-one billion, two hundred million, thirteen thousand, thirty-one".