978820 has 24 divisors (see below), whose sum is σ = 2079000. Its totient is φ = 387072.

The previous prime is 978799. The next prime is 978821. The reversal of 978820 is 28879.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 207936 + 770884 = 456^2 + 878^2 .

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (978821) by changing a digit.

978820 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1956 + ... + 2404.

It is an arithmetic number, because the mean of its divisors is an integer number (86625).

2⁹⁷⁸⁸²⁰ is an apocalyptic number.

It is an amenable number.

978820 is an abundant number, since it is smaller than the sum of its proper divisors (1100180).

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

978820 is a wasteful number, since it uses less digits than its factorization.

978820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 567 (or 565 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 978820 is about 989.3533241466. The cubic root of 978820 is about 99.2889561495.

The spelling of 978820 in words is "nine hundred seventy-eight thousand, eight hundred twenty".