31123200220 has 24 divisors (see below), whose sum is σ = 74695680864. Its totient is φ = 10670811456.

The previous prime is 31123200151. The next prime is 31123200253. The reversal of 31123200220 is 2200232113.

It is a junction number, because it is equal to n+sod(n) for n = 31123200194 and 31123200203.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111154147 + ... + 111154426.

It is an arithmetic number, because the mean of its divisors is an integer number (3112320036).

Almost surely, 2^31123200220 is an apocalyptic number.

It is an amenable number.

31123200220 is an abundant number, since it is smaller than the sum of its proper divisors (43572480644).

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

31123200220 is a wasteful number, since it uses less digits than its factorization.

31123200220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222308589 (or 222308587 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 31123200220 its reverse (2200232113), we get a palindrome (33323432333).

The spelling of 31123200220 in words is "thirty-one billion, one hundred twenty-three million, two hundred thousand, two hundred twenty".