809155081 has 24 divisors (see below), whose sum is σ = 965100744. Its totient is φ = 676166400.

The previous prime is 809155031. The next prime is 809155091. The reversal of 809155081 is 180551908.

It can be written as a sum of positive squares in 4 ways, for example, as 213014025 + 596141056 = 14595^2 + 24416^2 .

It is not a de Polignac number, because 809155081 - 2²¹ = 807057929 is a prime.

It is a super-2 number, since 2×809155081² = 1309463890216233122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 809155081.

It is not an unprimeable number, because it can be changed into a prime (809155021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 448381 + ... + 450181.

It is an arithmetic number, because the mean of its divisors is an integer number (40212531).

Almost surely, 2^809155081 is an apocalyptic number.

It is an amenable number.

809155081 is a deficient number, since it is larger than the sum of its proper divisors (155945663).

809155081 is a wasteful number, since it uses less digits than its factorization.

809155081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2041 (or 2034 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 37.

The square root of 809155081 is about 28445.6513548205. The cubic root of 809155081 is about 931.8455205322.

The spelling of 809155081 in words is "eight hundred nine million, one hundred fifty-five thousand, eighty-one".