978865 has 8 divisors (see below), whose sum is σ = 1184040. Its totient is φ = 776832.

The previous prime is 978863. The next prime is 978871. The reversal of 978865 is 568879.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 10609 + 968256 = 103^2 + 984^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 978865 - 2¹ = 978863 is a prime.

978865 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (978863) 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, 30 + ... + 1399.

It is an arithmetic number, because the mean of its divisors is an integer number (148005).

2⁹⁷⁸⁸⁶⁵ is an apocalyptic number.

It is an amenable number.

978865 is a deficient number, since it is larger than the sum of its proper divisors (205175).

978865 is a wasteful number, since it uses less digits than its factorization.

978865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1571.

The product of its digits is 120960, while the sum is 43.

The square root of 978865 is about 989.3760660133. The cubic root of 978865 is about 99.2904776872.

The spelling of 978865 in words is "nine hundred seventy-eight thousand, eight hundred sixty-five".