31123330220 has 12 divisors (see below), whose sum is σ = 65358993504. Its totient is φ = 12449332080.

The previous prime is 31123330181. The next prime is 31123330237. The reversal of 31123330220 is 2203332113.

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1556166511 = 31123330220 / (3 + 1 + 1 + 2 + 3 + 3 + 3 + 0 + 2 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 31123330192 and 31123330201.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 778083236 + ... + 778083275.

It is an arithmetic number, because the mean of its divisors is an integer number (5446582792).

Almost surely, 2^31123330220 is an apocalyptic number.

It is an amenable number.

31123330220 is an abundant number, since it is smaller than the sum of its proper divisors (34235663284).

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

31123330220 is a wasteful number, since it uses less digits than its factorization.

31123330220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1556166520 (or 1556166518 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 20.

Adding to 31123330220 its reverse (2203332113), we get a palindrome (33326662333).

The spelling of 31123330220 in words is "thirty-one billion, one hundred twenty-three million, three hundred thirty thousand, two hundred twenty".