31322120100 has 144 divisors (see below), whose sum is σ = 91871619840. Its totient is φ = 8238412800.

The previous prime is 31322120099. The next prime is 31322120111. The reversal of 31322120100 is 102122313.

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

It is a self number, because there is not a number n which added to its sum of digits gives 31322120100.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7617045 + ... + 7621155.

It is an arithmetic number, because the mean of its divisors is an integer number (637997360).

Almost surely, 2^31322120100 is an apocalyptic number.

31322120100 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31322120100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45935809920).

31322120100 is an abundant number, since it is smaller than the sum of its proper divisors (60549499740).

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

31322120100 is a wasteful number, since it uses less digits than its factorization.

31322120100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4470 (or 4463 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 31322120100 its reverse (102122313), we get a palindrome (31424242413).

The spelling of 31322120100 in words is "thirty-one billion, three hundred twenty-two million, one hundred twenty thousand, one hundred".