857978 has 16 divisors (see below), whose sum is σ = 1429920. Its totient is φ = 382800.

The previous prime is 857977. The next prime is 857981. The reversal of 857978 is 879758.

It is a super-2 number, since 2×857978² = 1472252496968, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (857977) 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, 968 + ... + 1628.

It is an arithmetic number, because the mean of its divisors is an integer number (89370).

2⁸⁵⁷⁹⁷⁸ is an apocalyptic number.

857978 is a deficient number, since it is larger than the sum of its proper divisors (571942).

857978 is a wasteful number, since it uses less digits than its factorization.

857978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 733.

The product of its digits is 141120, while the sum is 44.

The square root of 857978 is about 926.2710186549. The cubic root of 857978 is about 95.0222662489.

The spelling of 857978 in words is "eight hundred fifty-seven thousand, nine hundred seventy-eight".