1940009 has 4 divisors (see below), whose sum is σ = 1943040. Its totient is φ = 1936980.

The previous prime is 1939999. The next prime is 1940041. The reversal of 1940009 is 9000491.

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: 9000491 = 467 ⋅19273.

It is a cyclic number.

It is not a de Polignac number, because 1940009 - 2⁸ = 1939753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1940069) 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, 137 + ... + 1974.

It is an arithmetic number, because the mean of its divisors is an integer number (485760).

2^1940009 is an apocalyptic number.

It is an amenable number.

1940009 is a deficient number, since it is larger than the sum of its proper divisors (3031).

1940009 is an equidigital number, since it uses as much as digits as its factorization.

1940009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3030.

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 1940009 is about 1392.8420585264. The cubic root of 1940009 is about 124.7195633126.

The spelling of 1940009 in words is "one million, nine hundred forty thousand, nine".