31310040 has 64 divisors (see below), whose sum is σ = 94802400. Its totient is φ = 8271872.

The previous prime is 31310017. The next prime is 31310047. The reversal of 31310040 is 4001313.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 31309998 and 31310025.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31310047) 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 15 ways as a sum of consecutive naturals, for example, 12406 + ... + 14714.

Almost surely, 2^31310040 is an apocalyptic number.

31310040 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31310040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47401200).

31310040 is an abundant number, since it is smaller than the sum of its proper divisors (63492360).

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

31310040 is a wasteful number, since it uses less digits than its factorization.

31310040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2436 (or 2432 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 31310040 is about 5595.5375076931. The cubic root of 31310040 is about 315.1818551830.

Adding to 31310040 its reverse (4001313), we get a palindrome (35311353).

The spelling of 31310040 in words is "thirty-one million, three hundred ten thousand, forty".