309985457 has 4 divisors (see below), whose sum is σ = 310033920. Its totient is φ = 309936996.

The previous prime is 309985453. The next prime is 309985517. The reversal of 309985457 is 754589903.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 309985457 - 2² = 309985453 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (309985453) 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 in 3 ways as a sum of consecutive naturals, for example, 12857 + ... + 28022.

It is an arithmetic number, because the mean of its divisors is an integer number (77508480).

Almost surely, 2^309985457 is an apocalyptic number.

It is an amenable number.

309985457 is a deficient number, since it is larger than the sum of its proper divisors (48463).

309985457 is an equidigital number, since it uses as much as digits as its factorization.

309985457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48462.

The product of its (nonzero) digits is 1360800, while the sum is 50.

The square root of 309985457 is about 17606.4038633674. The cubic root of 309985457 is about 676.7793616515.

The spelling of 309985457 in words is "three hundred nine million, nine hundred eighty-five thousand, four hundred fifty-seven".