309864808513 has 48 divisors (see below), whose sum is σ = 359665272000. Its totient is φ = 266349667584.

The previous prime is 309864808507. The next prime is 309864808529. The reversal of 309864808513 is 315808468903.

It is a de Polignac number, because none of the positive numbers 2^k-309864808513 is a prime.

It is a Smith number, since the sum of its digits (55) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (309864838513) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 15315318 + ... + 15335536.

It is an arithmetic number, because the mean of its divisors is an integer number (7493026500).

Almost surely, 2^309864808513 is an apocalyptic number.

It is an amenable number.

309864808513 is a deficient number, since it is larger than the sum of its proper divisors (49800463487).

309864808513 is a wasteful number, since it uses less digits than its factorization.

309864808513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20386 (or 20373 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 55.

The spelling of 309864808513 in words is "three hundred nine billion, eight hundred sixty-four million, eight hundred eight thousand, five hundred thirteen".