55000009 has 4 divisors (see below), whose sum is σ = 55204740. Its totient is φ = 54795280.

The previous prime is 54999943. The next prime is 55000013. The reversal of 55000009 is 90000055.

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 14040009 + 40960000 = 3747^2 + 6400^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55000009 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 55000009.

It is not an unprimeable number, because it can be changed into a prime (55000069) 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, 101962 + ... + 102499.

It is an arithmetic number, because the mean of its divisors is an integer number (13801185).

Almost surely, 2^55000009 is an apocalyptic number.

It is an amenable number.

55000009 is a deficient number, since it is larger than the sum of its proper divisors (204731).

55000009 is a wasteful number, since it uses less digits than its factorization.

55000009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204730.

The product of its (nonzero) digits is 225, while the sum is 19.

The square root of 55000009 is about 7416.1990938755. The cubic root of 55000009 is about 380.2952668195.

The spelling of 55000009 in words is "fifty-five million, nine", and thus it is an aban number and an uban number.