55553209 has 4 divisors (see below), whose sum is σ = 57345280. Its totient is φ = 53761140.

The previous prime is 55553203. The next prime is 55553231. The reversal of 55553209 is 90235555.

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 55553209 - 2⁷ = 55553081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55553203) 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, 895989 + ... + 896050.

It is an arithmetic number, because the mean of its divisors is an integer number (14336320).

Almost surely, 2^55553209 is an apocalyptic number.

It is an amenable number.

55553209 is a deficient number, since it is larger than the sum of its proper divisors (1792071).

55553209 is a wasteful number, since it uses less digits than its factorization.

55553209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1792070.

The product of its (nonzero) digits is 33750, while the sum is 34.

The square root of 55553209 is about 7453.4025116050. The cubic root of 55553209 is about 381.5660418377.

The spelling of 55553209 in words is "fifty-five million, five hundred fifty-three thousand, two hundred nine".