28321640709 has 8 divisors (see below), whose sum is σ = 39404021952. Its totient is φ = 18060176640.

The previous prime is 28321640707. The next prime is 28321640783. The reversal of 28321640709 is 90704612382.

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

It is not a de Polignac number, because 28321640709 - 2¹ = 28321640707 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28321640707) 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, 205229212 + ... + 205229349.

It is an arithmetic number, because the mean of its divisors is an integer number (4925502744).

Almost surely, 2^28321640709 is an apocalyptic number.

It is an amenable number.

28321640709 is a deficient number, since it is larger than the sum of its proper divisors (11082381243).

28321640709 is a wasteful number, since it uses less digits than its factorization.

28321640709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410458587.

The product of its (nonzero) digits is 145152, while the sum is 42.

The spelling of 28321640709 in words is "twenty-eight billion, three hundred twenty-one million, six hundred forty thousand, seven hundred nine".