31312100320 has 144 divisors (see below), whose sum is σ = 79361983008. Its totient is φ = 11669806080.

The previous prime is 31312100293. The next prime is 31312100359. The reversal of 31312100320 is 2300121313.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 31312100294 and 31312100303.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3518917 + ... + 3527803.

It is an arithmetic number, because the mean of its divisors is an integer number (551124882).

Almost surely, 2^31312100320 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 31312100320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39680991504).

31312100320 is an abundant number, since it is smaller than the sum of its proper divisors (48049882688).

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

31312100320 is a wasteful number, since it uses less digits than its factorization.

31312100320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9001 (or 8974 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 16.

Adding to 31312100320 its reverse (2300121313), we get a palindrome (33612221633).

The spelling of 31312100320 in words is "thirty-one billion, three hundred twelve million, one hundred thousand, three hundred twenty".