31204402021 has 8 divisors (see below), whose sum is σ = 33818785784. Its totient is φ = 28620596160.

The previous prime is 31204402007. The next prime is 31204402087. The reversal of 31204402021 is 12020440213.

It can be written as a sum of positive squares in 4 ways, for example, as 3117993921 + 28086408100 = 55839^2 + 167590^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 31204402021 - 2⁵ = 31204401989 is a prime.

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 31204402021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31204472021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7642350 + ... + 7646431.

It is an arithmetic number, because the mean of its divisors is an integer number (4227348223).

Almost surely, 2^31204402021 is an apocalyptic number.

It is an amenable number.

31204402021 is a deficient number, since it is larger than the sum of its proper divisors (2614383763).

31204402021 is a wasteful number, since it uses less digits than its factorization.

31204402021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15288951.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 31204402021 its reverse (12020440213), we get a palindrome (43224842234).

The spelling of 31204402021 in words is "thirty-one billion, two hundred four million, four hundred two thousand, twenty-one".