31013240 has 32 divisors (see below), whose sum is σ = 70061760. Its totient is φ = 12355200.

The previous prime is 31013239. The next prime is 31013249. The reversal of 31013240 is 4231013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31013249) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9410 + ... + 12270.

It is an arithmetic number, because the mean of its divisors is an integer number (2189430).

Almost surely, 2^31013240 is an apocalyptic number.

It is an amenable number.

31013240 is an abundant number, since it is smaller than the sum of its proper divisors (39048520).

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

31013240 is a wasteful number, since it uses less digits than its factorization.

31013240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3143 (or 3139 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 31013240 is about 5568.9532230034. The cubic root of 31013240 is about 314.1827813251.

Adding to 31013240 its reverse (4231013), we get a palindrome (35244253).

The spelling of 31013240 in words is "thirty-one million, thirteen thousand, two hundred forty".