309640513 has 32 divisors (see below), whose sum is σ = 399974400. Its totient is φ = 232981056.

The previous prime is 309640489. The next prime is 309640517. The reversal of 309640513 is 315046903.

It is not a de Polignac number, because 309640513 - 2²⁵ = 276086081 is a prime.

It is not an unprimeable number, because it can be changed into a prime (309640517) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 499918 + ... + 500536.

It is an arithmetic number, because the mean of its divisors is an integer number (12499200).

Almost surely, 2^309640513 is an apocalyptic number.

It is an amenable number.

309640513 is a deficient number, since it is larger than the sum of its proper divisors (90333887).

309640513 is a wasteful number, since it uses less digits than its factorization.

309640513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 901.

The product of its (nonzero) digits is 9720, while the sum is 31.

The square root of 309640513 is about 17596.6051555407. The cubic root of 309640513 is about 676.5282341429.

The spelling of 309640513 in words is "three hundred nine million, six hundred forty thousand, five hundred thirteen".