31311111222 has 32 divisors (see below), whose sum is σ = 69677107200. Its totient is φ = 10422508104.

The previous prime is 31311111193. The next prime is 31311111229. The reversal of 31311111222 is 22211111313.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 31311111195 and 31311111204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31311111229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 364398 + ... + 442049.

It is an arithmetic number, because the mean of its divisors is an integer number (2177409600).

Almost surely, 2^31311111222 is an apocalyptic number.

31311111222 is an abundant number, since it is smaller than the sum of its proper divisors (38365995978).

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

31311111222 is a wasteful number, since it uses less digits than its factorization.

31311111222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 807177 (or 807171 counting only the distinct ones).

The product of its digits is 72, while the sum is 18.

Adding to 31311111222 its reverse (22211111313), we get a palindrome (53522222535).

Subtracting from 31311111222 its reverse (22211111313), we obtain a palindrome (9099999909).

The spelling of 31311111222 in words is "thirty-one billion, three hundred eleven million, one hundred eleven thousand, two hundred twenty-two".