3131640 has 48 divisors (see below), whose sum is σ = 10179000. Its totient is φ = 835008.

The previous prime is 3131629. The next prime is 3131641. The reversal of 3131640 is 461313.

3131640 = 157² + 158² + ... + 236².

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3131641) 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 11 ways as a sum of consecutive naturals, for example, 3990 + ... + 4709.

Almost surely, 2^3131640 is an apocalyptic number.

3131640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

3131640 is an abundant number, since it is smaller than the sum of its proper divisors (7047360).

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

3131640 is a wasteful number, since it uses less digits than its factorization.

3131640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8716 (or 8709 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 3131640 is about 1769.6440320019. The cubic root of 3131640 is about 146.3043628715.

Adding to 3131640 its reverse (461313), we get a palindrome (3592953).

It can be divided in two parts, 313 and 1640, that added together give a triangular number (1953 = T₆₂).

The spelling of 3131640 in words is "three million, one hundred thirty-one thousand, six hundred forty".