1800109 has 4 divisors (see below), whose sum is σ = 1842016. Its totient is φ = 1758204.

The previous prime is 1800103. The next prime is 1800119. The reversal of 1800109 is 9010081.

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-1800109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1800103) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20889 + ... + 20974.

It is an arithmetic number, because the mean of its divisors is an integer number (460504).

2^1800109 is an apocalyptic number.

It is an amenable number.

1800109 is a deficient number, since it is larger than the sum of its proper divisors (41907).

1800109 is an equidigital number, since it uses as much as digits as its factorization.

1800109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41906.

The product of its (nonzero) digits is 72, while the sum is 19.

The square root of 1800109 is about 1341.6814077865. The cubic root of 1800109 is about 121.6464952694.

The spelling of 1800109 in words is "one million, eight hundred thousand, one hundred nine".