1999009 has 4 divisors (see below), whose sum is σ = 2104240. Its totient is φ = 1893780.

The previous prime is 1999007. The next prime is 1999021. The reversal of 1999009 is 9009991.

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 not a de Polignac number, because 1999009 - 2¹ = 1999007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1999007) 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, 52587 + ... + 52624.

It is an arithmetic number, because the mean of its divisors is an integer number (526060).

2^1999009 is an apocalyptic number.

1999009 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1999009 is a deficient number, since it is larger than the sum of its proper divisors (105231).

1999009 is a wasteful number, since it uses less digits than its factorization.

1999009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105230.

The product of its (nonzero) digits is 6561, while the sum is 37.

The square root of 1999009 is about 1413.8631475500. The cubic root of 1999009 is about 125.9712918555.

The spelling of 1999009 in words is "one million, nine hundred ninety-nine thousand, nine".