21031013031 has 16 divisors (see below), whose sum is σ = 32136537600. Its totient is φ = 11984241888.

The previous prime is 21031013023. The next prime is 21031013041. The reversal of 21031013031 is 13031013012.

It is not a de Polignac number, because 21031013031 - 2³ = 21031013023 is a prime.

It is a super-2 number, since 2×21031013031² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21031013031.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031013011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1387276 + ... + 1402353.

It is an arithmetic number, because the mean of its divisors is an integer number (2008533600).

Almost surely, 2^21031013031 is an apocalyptic number.

21031013031 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21031013031 is a deficient number, since it is larger than the sum of its proper divisors (11105524569).

21031013031 is a wasteful number, since it uses less digits than its factorization.

21031013031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2789998.

The product of its (nonzero) digits is 54, while the sum is 15.

Adding to 21031013031 its reverse (13031013012), we get a palindrome (34062026043).

The spelling of 21031013031 in words is "twenty-one billion, thirty-one million, thirteen thousand, thirty-one".