31313687 has 2 divisors, whose sum is σ = 31313688. Its totient is φ = 31313686.

The previous prime is 31313683. The next prime is 31313701. The reversal of 31313687 is 78631313.

It is a weak prime.

It is an emirp because it is prime and its reverse (78631313) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31313687 - 2² = 31313683 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31313683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15656843 + 15656844.

It is an arithmetic number, because the mean of its divisors is an integer number (15656844).

Almost surely, 2^31313687 is an apocalyptic number.

31313687 is a deficient number, since it is larger than the sum of its proper divisors (1).

31313687 is an equidigital number, since it uses as much as digits as its factorization.

31313687 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 32.

The square root of 31313687 is about 5595.8633828928. The cubic root of 31313687 is about 315.1940921907.

The spelling of 31313687 in words is "thirty-one million, three hundred thirteen thousand, six hundred eighty-seven".