31313536 has 16 divisors (see below), whose sum is σ = 62382690. Its totient is φ = 15656704.

The previous prime is 31313531. The next prime is 31313537. The reversal of 31313536 is 63531313.

It can be written as a sum of positive squares in only one way, i.e., 30735936 + 577600 = 5544^2 + 760^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a super-4 number, since 4×31313536⁴ (a number of 31 digits) contains 4444 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31313536.

It is not an unprimeable number, because it can be changed into a prime (31313531) 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 as a sum of consecutive naturals, namely, 122191 + ... + 122446.

Almost surely, 2^31313536 is an apocalyptic number.

It is an amenable number.

31313536 is a deficient number, since it is larger than the sum of its proper divisors (31069154).

31313536 is an equidigital number, since it uses as much as digits as its factorization.

31313536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244651 (or 244639 counting only the distinct ones).

The product of its digits is 2430, while the sum is 25.

The square root of 31313536 is about 5595.8498907673. The cubic root of 31313536 is about 315.1935855498.

Adding to 31313536 its reverse (63531313), we get a palindrome (94844849).

The spelling of 31313536 in words is "thirty-one million, three hundred thirteen thousand, five hundred thirty-six".