820808331 has 32 divisors (see below), whose sum is σ = 1340333568. Its totient is φ = 436108800.

The previous prime is 820808327. The next prime is 820808347. The reversal of 820808331 is 133808028.

It is not a de Polignac number, because 820808331 - 2² = 820808327 is a prime.

It is a super-2 number, since 2×820808331² = 1347452632478011122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 820808292 and 820808301.

It is not an unprimeable number, because it can be changed into a prime (820808311) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15781 + ... + 43481.

It is an arithmetic number, because the mean of its divisors is an integer number (41885424).

Almost surely, 2^820808331 is an apocalyptic number.

820808331 is a deficient number, since it is larger than the sum of its proper divisors (519525237).

820808331 is a wasteful number, since it uses less digits than its factorization.

820808331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27811.

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 820808331 is about 28649.7527214460. The cubic root of 820808331 is about 936.2976181646.

The spelling of 820808331 in words is "eight hundred twenty million, eight hundred eight thousand, three hundred thirty-one".