31121212 has 12 divisors (see below), whose sum is σ = 54737200. Its totient is φ = 15482016.

The previous prime is 31121197. The next prime is 31121249. The reversal of 31121212 is 21212113.

It is a junction number, because it is equal to n+sod(n) for n = 31121192 and 31121201.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18753 + ... + 20344.

Almost surely, 2^31121212 is an apocalyptic number.

It is an amenable number.

31121212 is a deficient number, since it is larger than the sum of its proper divisors (23615988).

31121212 is a wasteful number, since it uses less digits than its factorization.

31121212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39300 (or 39298 counting only the distinct ones).

The product of its digits is 24, while the sum is 13.

The square root of 31121212 is about 5578.6389020979. The cubic root of 31121212 is about 314.5469661257.

Adding to 31121212 its reverse (21212113), we get a palindrome (52333325).

Subtracting from 31121212 its reverse (21212113), we obtain a palindrome (9909099).

The spelling of 31121212 in words is "thirty-one million, one hundred twenty-one thousand, two hundred twelve".