857686872 has 128 divisors (see below), whose sum is σ = 2525644800. Its totient is φ = 237619200.

The previous prime is 857686867. The next prime is 857686897. The reversal of 857686872 is 278686758.

It is a happy number.

857686872 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×857686872² = 1471253540802288768, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1645972 + ... + 1646492.

It is an arithmetic number, because the mean of its divisors is an integer number (19731600).

Almost surely, 2^857686872 is an apocalyptic number.

857686872 is a gapful number since it is divisible by the number (82) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 857686872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1262822400).

857686872 is an abundant number, since it is smaller than the sum of its proper divisors (1667957928).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

857686872 is a wasteful number, since it uses less digits than its factorization.

857686872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 817 (or 813 counting only the distinct ones).

The product of its digits is 9031680, while the sum is 57.

The square root of 857686872 is about 29286.2915371680. The cubic root of 857686872 is about 950.1151742172.

The spelling of 857686872 in words is "eight hundred fifty-seven million, six hundred eighty-six thousand, eight hundred seventy-two".