809155091 has 2 divisors, whose sum is σ = 809155092. Its totient is φ = 809155090.

The previous prime is 809155031. The next prime is 809155163. The reversal of 809155091 is 190551908.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 809155091 - 2⁶ = 809155027 is a prime.

It is a super-2 number, since 2×809155091² = 1309463922582436562, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (809155021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 404577545 + 404577546.

It is an arithmetic number, because the mean of its divisors is an integer number (404577546).

Almost surely, 2^809155091 is an apocalyptic number.

809155091 is a deficient number, since it is larger than the sum of its proper divisors (1).

809155091 is an equidigital number, since it uses as much as digits as its factorization.

809155091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16200, while the sum is 38.

The square root of 809155091 is about 28445.6515305943. The cubic root of 809155091 is about 931.8455243709.

The spelling of 809155091 in words is "eight hundred nine million, one hundred fifty-five thousand, ninety-one".