28239711857 has 64 divisors (see below), whose sum is σ = 37047435264. Its totient is φ = 20951377920.

The previous prime is 28239711833. The next prime is 28239711869. The reversal of 28239711857 is 75811793282.

It is a cyclic number.

It is not a de Polignac number, because 28239711857 - 2⁶ = 28239711793 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28239711799 and 28239711808.

It is not an unprimeable number, because it can be changed into a prime (28239711257) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 14168453 + ... + 14170445.

It is an arithmetic number, because the mean of its divisors is an integer number (578866176).

Almost surely, 2^28239711857 is an apocalyptic number.

It is an amenable number.

28239711857 is a deficient number, since it is larger than the sum of its proper divisors (8807723407).

28239711857 is a wasteful number, since it uses less digits than its factorization.

28239711857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2238.

The product of its digits is 1693440, while the sum is 53.

The spelling of 28239711857 in words is "twenty-eight billion, two hundred thirty-nine million, seven hundred eleven thousand, eight hundred fifty-seven".