309812873 has 2 divisors, whose sum is σ = 309812874. Its totient is φ = 309812872.

The previous prime is 309812857. The next prime is 309812903. The reversal of 309812873 is 378218903.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 273968704 + 35844169 = 16552^2 + 5987^2 .

It is a cyclic number.

It is not a de Polignac number, because 309812873 - 2⁴ = 309812857 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 309812873.

It is not a weakly prime, because it can be changed into another prime (309812843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154906436 + 154906437.

It is an arithmetic number, because the mean of its divisors is an integer number (154906437).

Almost surely, 2^309812873 is an apocalyptic number.

It is an amenable number.

309812873 is a deficient number, since it is larger than the sum of its proper divisors (1).

309812873 is an equidigital number, since it uses as much as digits as its factorization.

309812873 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72576, while the sum is 41.

The square root of 309812873 is about 17601.5020097718. The cubic root of 309812873 is about 676.6537396588.

The spelling of 309812873 in words is "three hundred nine million, eight hundred twelve thousand, eight hundred seventy-three".