31231101220 has 48 divisors (see below), whose sum is σ = 71568858816. Its totient is φ = 11353392000.

The previous prime is 31231101191. The next prime is 31231101259. The reversal of 31231101220 is 2210113213.

It is a junction number, because it is equal to n+sod(n) for n = 31231101194 and 31231101203.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 792790 + ... + 831250.

It is an arithmetic number, because the mean of its divisors is an integer number (1491017892).

Almost surely, 2^31231101220 is an apocalyptic number.

It is an amenable number.

31231101220 is an abundant number, since it is smaller than the sum of its proper divisors (40337757596).

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

31231101220 is a wasteful number, since it uses less digits than its factorization.

31231101220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42172 (or 42170 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 31231101220 its reverse (2210113213), we get a palindrome (33441214433).

The spelling of 31231101220 in words is "thirty-one billion, two hundred thirty-one million, one hundred one thousand, two hundred twenty".