12091809 has 16 divisors (see below), whose sum is σ = 17050880. Its totient is φ = 7601040.

The previous prime is 12091789. The next prime is 12091861. The reversal of 12091809 is 90819021.

It is not a de Polignac number, because 12091809 - 2⁹ = 12091297 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a zygodrome in base 6.

It is not an unprimeable number, because it can be changed into a prime (12091109) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17154 + ... + 17844.

It is an arithmetic number, because the mean of its divisors is an integer number (1065680).

Almost surely, 2^12091809 is an apocalyptic number.

12091809 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

12091809 is a deficient number, since it is larger than the sum of its proper divisors (4959071).

12091809 is a wasteful number, since it uses less digits than its factorization.

12091809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1020.

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 12091809 is about 3477.3278533955. The cubic root of 12091809 is about 229.5252273140.

The spelling of 12091809 in words is "twelve million, ninety-one thousand, eight hundred nine".