31245965809 has 2 divisors, whose sum is σ = 31245965810. Its totient is φ = 31245965808.

The previous prime is 31245965789. The next prime is 31245965843. The reversal of 31245965809 is 90856954213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30678573409 + 567392400 = 175153^2 + 23820^2 .

It is an emirp because it is prime and its reverse (90856954213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31245965809 - 2¹¹ = 31245963761 is a prime.

It is not a weakly prime, because it can be changed into another prime (31245965869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15622982904 + 15622982905.

It is an arithmetic number, because the mean of its divisors is an integer number (15622982905).

Almost surely, 2^31245965809 is an apocalyptic number.

It is an amenable number.

31245965809 is a deficient number, since it is larger than the sum of its proper divisors (1).

31245965809 is an equidigital number, since it uses as much as digits as its factorization.

31245965809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2332800, while the sum is 52.

The spelling of 31245965809 in words is "thirty-one billion, two hundred forty-five million, nine hundred sixty-five thousand, eight hundred nine".