820628868 has 48 divisors (see below), whose sum is σ = 2000428416. Its totient is φ = 261338880.

The previous prime is 820628857. The next prime is 820628873. The reversal of 820628868 is 868826028.

It is a super-2 number, since 2×820628868² = 1346863477989922848, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 380080 + ... + 382232.

It is an arithmetic number, because the mean of its divisors is an integer number (41675592).

Almost surely, 2^820628868 is an apocalyptic number.

It is an amenable number.

820628868 is an abundant number, since it is smaller than the sum of its proper divisors (1179799548).

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

820628868 is a wasteful number, since it uses less digits than its factorization.

820628868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3564 (or 3562 counting only the distinct ones).

The product of its (nonzero) digits is 589824, while the sum is 48.

The square root of 820628868 is about 28646.6205336685. The cubic root of 820628868 is about 936.2293752628.

The spelling of 820628868 in words is "eight hundred twenty million, six hundred twenty-eight thousand, eight hundred sixty-eight".