978857 has 16 divisors (see below), whose sum is σ = 1150848. Its totient is φ = 823680.

The previous prime is 978853. The next prime is 978863. The reversal of 978857 is 758879.

It is not a de Polignac number, because 978857 - 2² = 978853 is a prime.

It is a super-2 number, since 2×978857² = 1916322052898, which contains 22 as substring.

It is a Duffinian number.

Its product of digits (141120) is a multiple of the sum of its prime divisors (160).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (978851) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13373 + ... + 13445.

It is an arithmetic number, because the mean of its divisors is an integer number (71928).

2⁹⁷⁸⁸⁵⁷ is an apocalyptic number.

It is an amenable number.

978857 is a deficient number, since it is larger than the sum of its proper divisors (171991).

978857 is a wasteful number, since it uses less digits than its factorization.

978857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160.

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

The square root of 978857 is about 989.3720230530. The cubic root of 978857 is about 99.2902071950.

The spelling of 978857 in words is "nine hundred seventy-eight thousand, eight hundred fifty-seven".