31243136 has 16 divisors (see below), whose sum is σ = 62242440. Its totient is φ = 15621504.

The previous prime is 31243123. The next prime is 31243139. The reversal of 31243136 is 63134213.

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

It is a super-2 number, since 2×31243136² = 1952267094228992, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31243139) 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, 121916 + ... + 122171.

Almost surely, 2^31243136 is an apocalyptic number.

It is an amenable number.

31243136 is a deficient number, since it is larger than the sum of its proper divisors (30999304).

31243136 is an equidigital number, since it uses as much as digits as its factorization.

31243136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244101 (or 244089 counting only the distinct ones).

The product of its digits is 1296, while the sum is 23.

The square root of 31243136 is about 5589.5559752095. Note that the first 3 decimals coincide. The cubic root of 31243136 is about 314.9571991901.

Adding to 31243136 its reverse (63134213), we get a palindrome (94377349).

The spelling of 31243136 in words is "thirty-one million, two hundred forty-three thousand, one hundred thirty-six".