31120021005 has 32 divisors (see below), whose sum is σ = 50520879360. Its totient is φ = 16354652160.

The previous prime is 31120020937. The next prime is 31120021021. The reversal of 31120021005 is 50012002113.

It is not a de Polignac number, because 31120021005 - 2⁹ = 31120020493 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2243431 + ... + 2257259.

It is an arithmetic number, because the mean of its divisors is an integer number (1578777480).

Almost surely, 2^31120021005 is an apocalyptic number.

It is an amenable number.

31120021005 is a deficient number, since it is larger than the sum of its proper divisors (19400858355).

31120021005 is a wasteful number, since it uses less digits than its factorization.

31120021005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16021.

The product of its (nonzero) digits is 60, while the sum is 15.

Adding to 31120021005 its reverse (50012002113), we get a palindrome (81132023118).

The spelling of 31120021005 in words is "thirty-one billion, one hundred twenty million, twenty-one thousand, five".