820580866 has 16 divisors (see below), whose sum is σ = 1414845504. Its totient is φ = 349643664.

The previous prime is 820580833. The next prime is 820580921. The reversal of 820580866 is 668085028.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 166980 + ... + 171823.

It is an arithmetic number, because the mean of its divisors is an integer number (88427844).

Almost surely, 2^820580866 is an apocalyptic number.

820580866 is a deficient number, since it is larger than the sum of its proper divisors (594264638).

820580866 is a wasteful number, since it uses less digits than its factorization.

820580866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338985.

The product of its (nonzero) digits is 184320, while the sum is 43.

The square root of 820580866 is about 28645.7826913492. The cubic root of 820580866 is about 936.2111202551.

The spelling of 820580866 in words is "eight hundred twenty million, five hundred eighty thousand, eight hundred sixty-six".