31311122240 has 112 divisors (see below), whose sum is σ = 79477362000. Its totient is φ = 11708301312.

The previous prime is 31311122237. The next prime is 31311122251. The reversal of 31311122240 is 4222111313.

It can be written as a sum of positive squares in 8 ways, for example, as 5951196736 + 25359925504 = 77144^2 + 159248^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 791246 + ... + 829874.

Almost surely, 2^31311122240 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31311122240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39738681000).

31311122240 is an abundant number, since it is smaller than the sum of its proper divisors (48166239760).

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

31311122240 is a wasteful number, since it uses less digits than its factorization.

31311122240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38812 (or 38802 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 31311122240 its reverse (4222111313), we get a palindrome (35533233553).

The spelling of 31311122240 in words is "thirty-one billion, three hundred eleven million, one hundred twenty-two thousand, two hundred forty".