21031022031 has 16 divisors (see below), whose sum is σ = 29749918464. Its totient is φ = 13169684864.

The previous prime is 21031022011. The next prime is 21031022087. The reversal of 21031022031 is 13022013012.

It is a cyclic number.

It is not a de Polignac number, because 21031022031 - 2⁷ = 21031021903 is a prime.

It is a super-2 number, since 2×21031022031² (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 21031022031.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031022011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 384261 + ... + 435566.

It is an arithmetic number, because the mean of its divisors is an integer number (1859369904).

Almost surely, 2^21031022031 is an apocalyptic number.

21031022031 is a deficient number, since it is larger than the sum of its proper divisors (8718896433).

21031022031 is a wasteful number, since it uses less digits than its factorization.

21031022031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 820350.

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21031022031 its reverse (13022013012), we get a palindrome (34053035043).

The spelling of 21031022031 in words is "twenty-one billion, thirty-one million, twenty-two thousand, thirty-one".