810009091 has 2 divisors, whose sum is σ = 810009092. Its totient is φ = 810009090.

The previous prime is 810009089. The next prime is 810009113. The reversal of 810009091 is 190900018.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 810009091 - 2¹ = 810009089 is a prime.

It is a super-2 number, since 2×810009091² = 1312229455005292562, which contains 22 as substring.

Together with 810009089, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (810009391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405004545 + 405004546.

It is an arithmetic number, because the mean of its divisors is an integer number (405004546).

Almost surely, 2^810009091 is an apocalyptic number.

810009091 is a deficient number, since it is larger than the sum of its proper divisors (1).

810009091 is an equidigital number, since it uses as much as digits as its factorization.

810009091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 28.

The square root of 810009091 is about 28460.6586536573. The cubic root of 810009091 is about 932.1732391621.

The spelling of 810009091 in words is "eight hundred ten million, nine thousand, ninety-one".