309728847 has 8 divisors (see below), whose sum is σ = 415134720. Its totient is φ = 205404440.

The previous prime is 309728803. The next prime is 309728863. The reversal of 309728847 is 748827903.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 309728847 - 2¹¹ = 309726799 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 309728796 and 309728805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (309728897) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 269697 + ... + 270842.

It is an arithmetic number, because the mean of its divisors is an integer number (51891840).

Almost surely, 2^309728847 is an apocalyptic number.

309728847 is a deficient number, since it is larger than the sum of its proper divisors (105405873).

309728847 is a wasteful number, since it uses less digits than its factorization.

309728847 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 540733.

The product of its (nonzero) digits is 677376, while the sum is 48.

The square root of 309728847 is about 17599.1149493377. The cubic root of 309728847 is about 676.5925611723.

The spelling of 309728847 in words is "three hundred nine million, seven hundred twenty-eight thousand, eight hundred forty-seven".