31213012 has 24 divisors (see below), whose sum is σ = 56548800. Its totient is φ = 15064896.

The previous prime is 31213009. The next prime is 31213027. The reversal of 31213012 is 21031213.

It is a super-2 number, since 2×31213012² = 1948504236224288, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31212983 and 31213001.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14289 + ... + 16327.

It is an arithmetic number, because the mean of its divisors is an integer number (2356200).

Almost surely, 2^31213012 is an apocalyptic number.

It is an amenable number.

31213012 is a deficient number, since it is larger than the sum of its proper divisors (25335788).

31213012 is a wasteful number, since it uses less digits than its factorization.

31213012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2175 (or 2173 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 31213012 is about 5586.8606569343. The cubic root of 31213012 is about 314.8559415186.

Adding to 31213012 its reverse (21031213), we get a palindrome (52244225).

The spelling of 31213012 in words is "thirty-one million, two hundred thirteen thousand, twelve".