31103212021 has 48 divisors (see below), whose sum is σ = 39166934400. Its totient is φ = 24548614272.

The previous prime is 31103212013. The next prime is 31103212031. The reversal of 31103212021 is 12021230113.

It is not a de Polignac number, because 31103212021 - 2³ = 31103212013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31103211986 and 31103212004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31103212031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5375496 + ... + 5381278.

It is an arithmetic number, because the mean of its divisors is an integer number (815977800).

Almost surely, 2^31103212021 is an apocalyptic number.

It is an amenable number.

31103212021 is a deficient number, since it is larger than the sum of its proper divisors (8063722379).

31103212021 is a wasteful number, since it uses less digits than its factorization.

31103212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5978 (or 5971 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 31103212021 its reverse (12021230113), we get a palindrome (43124442134).

The spelling of 31103212021 in words is "thirty-one billion, one hundred three million, two hundred twelve thousand, twenty-one".