1109809 has 4 divisors (see below), whose sum is σ = 1168240. Its totient is φ = 1051380.

The previous prime is 1109791. The next prime is 1109813. The reversal of 1109809 is 9089011.

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 a de Polignac number, because none of the positive numbers 2^k-1109809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1109839) 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 in 3 ways as a sum of consecutive naturals, for example, 29187 + ... + 29224.

It is an arithmetic number, because the mean of its divisors is an integer number (292060).

2^1109809 is an apocalyptic number.

1109809 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1109809 is a deficient number, since it is larger than the sum of its proper divisors (58431).

1109809 is an equidigital number, since it uses as much as digits as its factorization.

1109809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58430.

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

The square root of 1109809 is about 1053.4747267970. The cubic root of 1109809 is about 103.5339414302.

The spelling of 1109809 in words is "one million, one hundred nine thousand, eight hundred nine".