820587978 has 24 divisors (see below), whose sum is σ = 2031932448. Its totient is φ = 234453672.

The previous prime is 820587917. The next prime is 820587983. The reversal of 820587978 is 879785028.

820587978 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3256176 + ... + 3256427.

It is an arithmetic number, because the mean of its divisors is an integer number (84663852).

Almost surely, 2^820587978 is an apocalyptic number.

820587978 is an abundant number, since it is smaller than the sum of its proper divisors (1211344470).

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

820587978 is a wasteful number, since it uses less digits than its factorization.

820587978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6512618 (or 6512615 counting only the distinct ones).

The product of its (nonzero) digits is 2257920, while the sum is 54.

The square root of 820587978 is about 28645.9068280269. The cubic root of 820587978 is about 936.2138249710.

The spelling of 820587978 in words is "eight hundred twenty million, five hundred eighty-seven thousand, nine hundred seventy-eight".