820879801 has 9 divisors (see below), whose sum is σ = 955134351. Its totient is φ = 703439352.

The previous prime is 820879793. The next prime is 820879811. The reversal of 820879801 is 108978028.

The square root of 820879801 is 28651.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 340218025 + 480661776 = 18445^2 + 21924^2 .

It is not a de Polignac number, because 820879801 - 2³ = 820879793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820879811) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 198511 + ... + 202603.

It is an arithmetic number, because the mean of its divisors is an integer number (106126039).

Almost surely, 2^820879801 is an apocalyptic number.

820879801 is the 28651-st square number.

820879801 is the 14326-th centered octagonal number.

It is an amenable number.

820879801 is a deficient number, since it is larger than the sum of its proper divisors (134254550).

820879801 is an frugal number, since it uses more digits than its factorization.

820879801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8200 (or 4100 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 43.

The cubic root of 820879801 is about 936.3247926974.

The spelling of 820879801 in words is "eight hundred twenty million, eight hundred seventy-nine thousand, eight hundred one".