31311312 has 20 divisors (see below), whose sum is σ = 80887680. Its totient is φ = 10437088.

The previous prime is 31311281. The next prime is 31311323. The reversal of 31311312 is 21311313.

It is a super-2 number, since 2×31311312² = 1960796518322688, which contains 22 as substring.

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 = 31311291 and 31311300.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 326112 + ... + 326207.

It is an arithmetic number, because the mean of its divisors is an integer number (4044384).

Almost surely, 2^31311312 is an apocalyptic number.

It is an amenable number.

31311312 is an abundant number, since it is smaller than the sum of its proper divisors (49576368).

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

31311312 is a wasteful number, since it uses less digits than its factorization.

31311312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 652330 (or 652324 counting only the distinct ones).

The product of its digits is 54, while the sum is 15.

The square root of 31311312 is about 5595.6511685415. The cubic root of 31311312 is about 315.1861233122.

Adding to 31311312 its reverse (21311313), we get a palindrome (52622625).

Subtracting from 31311312 its reverse (21311313), we obtain a palindrome (9999999).

The spelling of 31311312 in words is "thirty-one million, three hundred eleven thousand, three hundred twelve".