31097993 has 2 divisors, whose sum is σ = 31097994. Its totient is φ = 31097992.

The previous prime is 31097977. The next prime is 31097999. The reversal of 31097993 is 39979013.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23931664 + 7166329 = 4892^2 + 2677^2 .

It is a cyclic number.

It is not a de Polignac number, because 31097993 - 2⁴ = 31097977 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31097993.

It is not a weakly prime, because it can be changed into another prime (31097999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15548996 + 15548997.

It is an arithmetic number, because the mean of its divisors is an integer number (15548997).

Almost surely, 2^31097993 is an apocalyptic number.

It is an amenable number.

31097993 is a deficient number, since it is larger than the sum of its proper divisors (1).

31097993 is an equidigital number, since it uses as much as digits as its factorization.

31097993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 45927, while the sum is 41.

The square root of 31097993 is about 5576.5574506141. The cubic root of 31097993 is about 314.4687206395.

The spelling of 31097993 in words is "thirty-one million, ninety-seven thousand, nine hundred ninety-three".