31103030021 has 16 divisors (see below), whose sum is σ = 36518880384. Its totient is φ = 25930787904.

The previous prime is 31103030011. The next prime is 31103030047. The reversal of 31103030021 is 12003030113.

It is not a de Polignac number, because 31103030021 - 2¹⁴ = 31103013637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31103029978 and 31103030005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31103030011) 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, 855806 + ... + 891408.

It is an arithmetic number, because the mean of its divisors is an integer number (2282430024).

Almost surely, 2^31103030021 is an apocalyptic number.

It is an amenable number.

31103030021 is a deficient number, since it is larger than the sum of its proper divisors (5415850363).

31103030021 is a wasteful number, since it uses less digits than its factorization.

31103030021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39020.

The product of its (nonzero) digits is 54, while the sum is 14.

Adding to 31103030021 its reverse (12003030113), we get a palindrome (43106060134).

The spelling of 31103030021 in words is "thirty-one billion, one hundred three million, thirty thousand, twenty-one".