31440730 has 16 divisors (see below), whose sum is σ = 56701800. Its totient is φ = 12552192.

The previous prime is 31440691. The next prime is 31440733. The reversal of 31440730 is 3704413.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 27910089 + 3530641 = 5283^2 + 1879^2 .

It is not an unprimeable number, because it can be changed into a prime (31440733) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3046 + ... + 8494.

Almost surely, 2^31440730 is an apocalyptic number.

31440730 is a deficient number, since it is larger than the sum of its proper divisors (25261070).

31440730 is a wasteful number, since it uses less digits than its factorization.

31440730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6033.

The product of its (nonzero) digits is 1008, while the sum is 22.

The square root of 31440730 is about 5607.2034027668. The cubic root of 31440730 is about 315.6197758179.

The spelling of 31440730 in words is "thirty-one million, four hundred forty thousand, seven hundred thirty".