31308040 has 32 divisors (see below), whose sum is σ = 71009280. Its totient is φ = 12422592.

The previous prime is 31308019. The next prime is 31308049. The reversal of 31308040 is 4080313.

It is a junction number, because it is equal to n+sod(n) for n = 31307999 and 31308017.

It is not an unprimeable number, because it can be changed into a prime (31308049) by changing a digit.

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, 1999 + ... + 8161.

It is an arithmetic number, because the mean of its divisors is an integer number (2219040).

Almost surely, 2^31308040 is an apocalyptic number.

It is an amenable number.

31308040 is an abundant number, since it is smaller than the sum of its proper divisors (39701240).

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

31308040 is a wasteful number, since it uses less digits than its factorization.

31308040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6301 (or 6297 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 31308040 is about 5595.3587909981. The cubic root of 31308040 is about 315.1751440542.

Adding to 31308040 its reverse (4080313), we get a palindrome (35388353).

The spelling of 31308040 in words is "thirty-one million, three hundred eight thousand, forty".