21010220031 has 16 divisors (see below), whose sum is σ = 28731977568. Its totient is φ = 13648473600.

The previous prime is 21010220027. The next prime is 21010220039. The reversal of 21010220031 is 13002201012.

It is not a de Polignac number, because 21010220031 - 2² = 21010220027 is a prime.

It is a super-2 number, since 2×21010220031² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21010219989 and 21010220016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010220039) 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, 3046 + ... + 205011.

It is an arithmetic number, because the mean of its divisors is an integer number (1795748598).

Almost surely, 2^21010220031 is an apocalyptic number.

21010220031 is a deficient number, since it is larger than the sum of its proper divisors (7721757537).

21010220031 is a wasteful number, since it uses less digits than its factorization.

21010220031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208922.

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 21010220031 its reverse (13002201012), we get a palindrome (34012421043).

The spelling of 21010220031 in words is "twenty-one billion, ten million, two hundred twenty thousand, thirty-one".