31325440 has 36 divisors (see below), whose sum is σ = 75037284. Its totient is φ = 12529664.

The previous prime is 31325429. The next prime is 31325447. The reversal of 31325440 is 4452313.

It can be written as a sum of positive squares in 2 ways, for example, as 18249984 + 13075456 = 4272^2 + 3616^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31325447) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10957 + ... + 13516.

It is an arithmetic number, because the mean of its divisors is an integer number (2084369).

Almost surely, 2^31325440 is an apocalyptic number.

It is an amenable number.

31325440 is an abundant number, since it is smaller than the sum of its proper divisors (43711844).

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

31325440 is an equidigital number, since it uses as much as digits as its factorization.

31325440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24494 (or 24480 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 31325440 is about 5596.9134350997. The cubic root of 31325440 is about 315.2335213046.

Adding to 31325440 its reverse (4452313), we get a palindrome (35777753).

The spelling of 31325440 in words is "thirty-one million, three hundred twenty-five thousand, four hundred forty".