31245140 has 24 divisors (see below), whose sum is σ = 65802240. Its totient is φ = 12462368.

The previous prime is 31245121. The next prime is 31245163. The reversal of 31245140 is 4154213.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 5621 + ... + 9699.

It is an arithmetic number, because the mean of its divisors is an integer number (2741760).

Almost surely, 2^31245140 is an apocalyptic number.

It is an amenable number.

31245140 is an abundant number, since it is smaller than the sum of its proper divisors (34557100).

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

31245140 is a wasteful number, since it uses less digits than its factorization.

31245140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4471 (or 4469 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 31245140 is about 5589.7352352325. The cubic root of 31245140 is about 314.9639330504.

Adding to 31245140 its reverse (4154213), we get a palindrome (35399353).

The spelling of 31245140 in words is "thirty-one million, two hundred forty-five thousand, one hundred forty".