31312212 has 48 divisors (see below), whose sum is σ = 75841920. Its totient is φ = 10046592.

The previous prime is 31312163. The next prime is 31312217. The reversal of 31312212 is 21221313.

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 = 31312191 and 31312200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31312217) 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, 48073 + ... + 48719.

It is an arithmetic number, because the mean of its divisors is an integer number (1580040).

Almost surely, 2^31312212 is an apocalyptic number.

It is an amenable number.

31312212 is an abundant number, since it is smaller than the sum of its proper divisors (44529708).

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

31312212 is a wasteful number, since it uses less digits than its factorization.

31312212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800 (or 798 counting only the distinct ones).

The product of its digits is 72, while the sum is 15.

The square root of 31312212 is about 5595.7315875585. The cubic root of 31312212 is about 315.1891431452.

Adding to 31312212 its reverse (21221313), we get a palindrome (52533525).

The spelling of 31312212 in words is "thirty-one million, three hundred twelve thousand, two hundred twelve".