31313656 has 64 divisors (see below), whose sum is σ = 66977280. Its totient is φ = 13601280.

The previous prime is 31313641. The next prime is 31313683. The reversal of 31313656 is 65631313.

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 15 ways as a sum of consecutive naturals, for example, 277056 + ... + 277168.

It is an arithmetic number, because the mean of its divisors is an integer number (1046520).

Almost surely, 2^31313656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31313656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33488640).

31313656 is an abundant number, since it is smaller than the sum of its proper divisors (35663624).

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

31313656 is a wasteful number, since it uses less digits than its factorization.

31313656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244 (or 240 counting only the distinct ones).

The product of its digits is 4860, while the sum is 28.

The square root of 31313656 is about 5595.8606129889. The cubic root of 31313656 is about 315.1939881784.

Adding to 31313656 its reverse (65631313), we get a palindrome (96944969).

The spelling of 31313656 in words is "thirty-one million, three hundred thirteen thousand, six hundred fifty-six".