31012540 has 48 divisors (see below), whose sum is σ = 70630560. Its totient is φ = 11370240.

The previous prime is 31012483. The next prime is 31012561. The reversal of 31012540 is 4521013.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46731 + ... + 47389.

It is an arithmetic number, because the mean of its divisors is an integer number (1471470).

Almost surely, 2^31012540 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31012540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35315280).

31012540 is an abundant number, since it is smaller than the sum of its proper divisors (39618020).

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

31012540 is a wasteful number, since it uses less digits than its factorization.

31012540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 862 (or 860 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 31012540 is about 5568.8903742128. The cubic root of 31012540 is about 314.1804175003.

Adding to 31012540 its reverse (4521013), we get a palindrome (35533553).

The spelling of 31012540 in words is "thirty-one million, twelve thousand, five hundred forty".