31131100000 has 576 divisors, whose sum is σ = 103187395584. Its totient is φ = 8928000000.

The previous prime is 31131099983. The next prime is 31131100019. The reversal of 31131100000 is 113113.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a self number, because there is not a number n which added to its sum of digits gives 31131100000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 100099845 + ... + 100100155.

It is an arithmetic number, because the mean of its divisors is an integer number (179144784).

Almost surely, 2^31131100000 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 31131100000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51593697792).

31131100000 is an abundant number, since it is smaller than the sum of its proper divisors (72056295584).

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

31131100000 is a wasteful number, since it uses less digits than its factorization.

31131100000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377 (or 349 counting only the distinct ones).

The product of its (nonzero) digits is 9, while the sum is 10.

Adding to 31131100000 its reverse (113113), we get a palindrome (31131213113).

It can be divided in two parts, 31131 and 100000, that added together give a palindrome (131131).

The spelling of 31131100000 in words is "thirty-one billion, one hundred thirty-one million, one hundred thousand".