31121213023 has 4 divisors (see below), whose sum is σ = 31307567760. Its totient is φ = 30934858288.

The previous prime is 31121213021. The next prime is 31121213119. The reversal of 31121213023 is 32031212113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32031212113 = 1499 ⋅21368387.

It is a cyclic number.

It is not a de Polignac number, because 31121213023 - 2¹ = 31121213021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31121213021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 93177118 + ... + 93177451.

It is an arithmetic number, because the mean of its divisors is an integer number (7826891940).

Almost surely, 2^31121213023 is an apocalyptic number.

31121213023 is a deficient number, since it is larger than the sum of its proper divisors (186354737).

31121213023 is a wasteful number, since it uses less digits than its factorization.

31121213023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186354736.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 31121213023 its reverse (32031212113), we get a palindrome (63152425136).

The spelling of 31121213023 in words is "thirty-one billion, one hundred twenty-one million, two hundred thirteen thousand, twenty-three".