820286660 has 24 divisors (see below), whose sum is σ = 1778171136. Its totient is φ = 317530080.

The previous prime is 820286641. The next prime is 820286693. The reversal of 820286660 is 66682028.

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, 660902 + ... + 662141.

It is an arithmetic number, because the mean of its divisors is an integer number (74090464).

Almost surely, 2^820286660 is an apocalyptic number.

It is an amenable number.

820286660 is an abundant number, since it is smaller than the sum of its proper divisors (957884476).

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

820286660 is a wasteful number, since it uses less digits than its factorization.

820286660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1323083 (or 1323081 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 38.

The square root of 820286660 is about 28640.6469898988. The cubic root of 820286660 is about 936.0992190947.

It can be divided in two parts, 82028 and 6660, that added together give a palindrome (88688).

The spelling of 820286660 in words is "eight hundred twenty million, two hundred eighty-six thousand, six hundred sixty".