55644209 has 2 divisors, whose sum is σ = 55644210. Its totient is φ = 55644208.

The previous prime is 55644187. The next prime is 55644227. The reversal of 55644209 is 90244655.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53333809 + 2310400 = 7303^2 + 1520^2 .

It is a cyclic number.

It is not a de Polignac number, because 55644209 - 2¹⁶ = 55578673 is a prime.

It is not a weakly prime, because it can be changed into another prime (55644269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27822104 + 27822105.

It is an arithmetic number, because the mean of its divisors is an integer number (27822105).

Almost surely, 2^55644209 is an apocalyptic number.

It is an amenable number.

55644209 is a deficient number, since it is larger than the sum of its proper divisors (1).

55644209 is an equidigital number, since it uses as much as digits as its factorization.

55644209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 43200, while the sum is 35.

The square root of 55644209 is about 7459.5046082163. The cubic root of 55644209 is about 381.7742720394.

The spelling of 55644209 in words is "fifty-five million, six hundred forty-four thousand, two hundred nine".