809905097 has 4 divisors (see below), whose sum is σ = 810047760. Its totient is φ = 809762436.

The previous prime is 809905091. The next prime is 809905111. The reversal of 809905097 is 790509908.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 809905097 - 2²⁸ = 541469641 is a prime.

It is a super-2 number, since 2×809905097² = 1311892532293158818, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (809905091) 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 3 ways as a sum of consecutive naturals, for example, 62447 + ... + 74292.

It is an arithmetic number, because the mean of its divisors is an integer number (202511940).

Almost surely, 2^809905097 is an apocalyptic number.

It is an amenable number.

809905097 is a deficient number, since it is larger than the sum of its proper divisors (142663).

809905097 is a wasteful number, since it uses less digits than its factorization.

809905097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142662.

The product of its (nonzero) digits is 204120, while the sum is 47.

The square root of 809905097 is about 28458.8316169164. The cubic root of 809905097 is about 932.1333447239.

The spelling of 809905097 in words is "eight hundred nine million, nine hundred five thousand, ninety-seven".