31309199993 has 2 divisors, whose sum is σ = 31309199994. Its totient is φ = 31309199992.

The previous prime is 31309199969. The next prime is 31309200011. The reversal of 31309199993 is 39999190313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29624261689 + 1684938304 = 172117^2 + 41048^2 .

It is a cyclic number.

It is not a de Polignac number, because 31309199993 - 2¹⁶ = 31309134457 is a prime.

It is not a weakly prime, because it can be changed into another prime (31309999993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15654599996 + 15654599997.

It is an arithmetic number, because the mean of its divisors is an integer number (15654599997).

Almost surely, 2^31309199993 is an apocalyptic number.

It is an amenable number.

31309199993 is a deficient number, since it is larger than the sum of its proper divisors (1).

31309199993 is an equidigital number, since it uses as much as digits as its factorization.

31309199993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1594323, while the sum is 56.

The spelling of 31309199993 in words is "thirty-one billion, three hundred nine million, one hundred ninety-nine thousand, nine hundred ninety-three".