1984009 has 4 divisors (see below), whose sum is σ = 1996804. Its totient is φ = 1971216.

The previous prime is 1984007. The next prime is 1984013. The reversal of 1984009 is 9004891.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 366025 + 1617984 = 605^2 + 1272^2 .

It is a 6-Lehmer number, since φ(1984009) divides (1984009-1)⁶.

It is a cyclic number.

It is not a de Polignac number, because 1984009 - 2¹ = 1984007 is a prime.

It is a Duffinian number.

1984009 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1984007) 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, 6162 + ... + 6475.

It is an arithmetic number, because the mean of its divisors is an integer number (499201).

2^1984009 is an apocalyptic number.

It is an amenable number.

1984009 is a deficient number, since it is larger than the sum of its proper divisors (12795).

1984009 is a wasteful number, since it uses less digits than its factorization.

1984009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12794.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 1984009 is about 1408.5485437144. The cubic root of 1984009 is about 125.6554160982.

The spelling of 1984009 in words is "one million, nine hundred eighty-four thousand, nine".