31000220 has 24 divisors (see below), whose sum is σ = 65436000. Its totient is φ = 12336192.

The previous prime is 31000199. The next prime is 31000237. The reversal of 31000220 is 2200013.

It is a super-2 number, since 2×31000220² = 1922027280096800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31000198 and 31000207.

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, 86 + ... + 7874.

It is an arithmetic number, because the mean of its divisors is an integer number (2726500).

Almost surely, 2^31000220 is an apocalyptic number.

It is an amenable number.

31000220 is an abundant number, since it is smaller than the sum of its proper divisors (34435780).

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

31000220 is a wasteful number, since it uses less digits than its factorization.

31000220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7997 (or 7995 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 8.

The square root of 31000220 is about 5567.7841193782. The cubic root of 31000220 is about 314.1388083597.

Adding to 31000220 its reverse (2200013), we get a palindrome (33200233).

The spelling of 31000220 in words is "thirty-one million, two hundred twenty", and thus it is an aban number.