1918009 has 4 divisors (see below), whose sum is σ = 1946704. Its totient is φ = 1889316.

The previous prime is 1918003. The next prime is 1918013. The reversal of 1918009 is 9008191.

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, and also an emirpimes, since its reverse is a distinct semiprime: 9008191 = 541 ⋅16651.

It is a cyclic number.

It is not a de Polignac number, because 1918009 - 2⁵ = 1917977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1918003) 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, 14247 + ... + 14380.

It is an arithmetic number, because the mean of its divisors is an integer number (486676).

2^1918009 is an apocalyptic number.

It is an amenable number.

1918009 is a deficient number, since it is larger than the sum of its proper divisors (28695).

1918009 is an equidigital number, since it uses as much as digits as its factorization.

1918009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28694.

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

The square root of 1918009 is about 1384.9220194654. The cubic root of 1918009 is about 124.2463235744.

The spelling of 1918009 in words is "one million, nine hundred eighteen thousand, nine".