31012243220 has 48 divisors (see below), whose sum is σ = 75152034048. Its totient is φ = 10529533440.

The previous prime is 31012243193. The next prime is 31012243313. The reversal of 31012243220 is 2234221013.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 31012243192 and 31012243201.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1060901 + ... + 1089740.

It is an arithmetic number, because the mean of its divisors is an integer number (1565667376).

Almost surely, 2^31012243220 is an apocalyptic number.

It is an amenable number.

31012243220 is an abundant number, since it is smaller than the sum of its proper divisors (44139790828).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31012243220 is a wasteful number, since it uses less digits than its factorization.

31012243220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2150760 (or 2150758 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 31012243220 its reverse (2234221013), we get a palindrome (33246464233).

The spelling of 31012243220 in words is "thirty-one billion, twelve million, two hundred forty-three thousand, two hundred twenty".