31121303121 has 6 divisors (see below), whose sum is σ = 44952993410. Its totient is φ = 20747535408.

The previous prime is 31121303119. The next prime is 31121303149. The reversal of 31121303121 is 12130312113.

It can be written as a sum of positive squares in only one way, i.e., 17650451025 + 13470852096 = 132855^2 + 116064^2 .

It is not a de Polignac number, because 31121303121 - 2¹ = 31121303119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31121303094 and 31121303103.

It is not an unprimeable number, because it can be changed into a prime (31121303111) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1728961276 + ... + 1728961293.

Almost surely, 2^31121303121 is an apocalyptic number.

It is an amenable number.

31121303121 is a deficient number, since it is larger than the sum of its proper divisors (13831690289).

31121303121 is a wasteful number, since it uses less digits than its factorization.

31121303121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3457922575 (or 3457922572 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 31121303121 its reverse (12130312113), we get a palindrome (43251615234).

The spelling of 31121303121 in words is "thirty-one billion, one hundred twenty-one million, three hundred three thousand, one hundred twenty-one".