31631312 has 40 divisors (see below), whose sum is σ = 62886600. Its totient is φ = 15409152.

The previous prime is 31631297. The next prime is 31631317. The reversal of 31631312 is 21313613.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6270016 + 25361296 = 2504^2 + 5036^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31631317) by changing a digit.

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, 138014 + ... + 138242.

It is an arithmetic number, because the mean of its divisors is an integer number (1572165).

Almost surely, 2^31631312 is an apocalyptic number.

It is an amenable number.

31631312 is a deficient number, since it is larger than the sum of its proper divisors (31255288).

31631312 is a wasteful number, since it uses less digits than its factorization.

31631312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 423 (or 417 counting only the distinct ones).

The product of its digits is 324, while the sum is 20.

The square root of 31631312 is about 5624.1721168542. The cubic root of 31631312 is about 316.2562147851.

Adding to 31631312 its reverse (21313613), we get a palindrome (52944925).

The spelling of 31631312 in words is "thirty-one million, six hundred thirty-one thousand, three hundred twelve".