31311100020 has 24 divisors (see below), whose sum is σ = 87671080224. Its totient is φ = 8349626656.

The previous prime is 31311100003. The next prime is 31311100099. The reversal of 31311100020 is 2000111313.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 31311099969 and 31311100005.

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 7 ways as a sum of consecutive naturals, for example, 260925774 + ... + 260925893.

It is an arithmetic number, because the mean of its divisors is an integer number (3652961676).

Almost surely, 2^31311100020 is an apocalyptic number.

31311100020 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31311100020 is an abundant number, since it is smaller than the sum of its proper divisors (56359980204).

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

31311100020 is a wasteful number, since it uses less digits than its factorization.

31311100020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 521851679 (or 521851677 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 12.

Adding to 31311100020 its reverse (2000111313), we get a palindrome (33311211333).

The spelling of 31311100020 in words is "thirty-one billion, three hundred eleven million, one hundred thousand, twenty".