79857 has 12 divisors (see below), whose sum is σ = 121680. Its totient is φ = 50328.

The previous prime is 79847. The next prime is 79861. The reversal of 79857 is 75897.

It is not a de Polignac number, because 79857 - 2⁴ = 79841 is a prime.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (79817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 63 + ... + 404.

It is an arithmetic number, because the mean of its divisors is an integer number (10140).

2⁷⁹⁸⁵⁷ is an apocalyptic number.

It is an amenable number.

79857 is a deficient number, since it is larger than the sum of its proper divisors (41823).

79857 is a wasteful number, since it uses less digits than its factorization.

79857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 492 (or 489 counting only the distinct ones).

The product of its digits is 17640, while the sum is 36.

The square root of 79857 is about 282.5898087334. The cubic root of 79857 is about 43.0630048081.

The spelling of 79857 in words is "seventy-nine thousand, eight hundred fifty-seven".