55236809 has 2 divisors, whose sum is σ = 55236810. Its totient is φ = 55236808.

The previous prime is 55236763. The next prime is 55236829. The reversal of 55236809 is 90863255.

55236809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50410000 + 4826809 = 7100^2 + 2197^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55236809 is a prime.

It is a super-2 number, since 2×55236809² = 6102210137004962, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (55236829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27618404 + 27618405.

It is an arithmetic number, because the mean of its divisors is an integer number (27618405).

Almost surely, 2^55236809 is an apocalyptic number.

It is an amenable number.

55236809 is a deficient number, since it is larger than the sum of its proper divisors (1).

55236809 is an equidigital number, since it uses as much as digits as its factorization.

55236809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64800, while the sum is 38.

The square root of 55236809 is about 7432.1469980080. The cubic root of 55236809 is about 380.8402666481.

The spelling of 55236809 in words is "fifty-five million, two hundred thirty-six thousand, eight hundred nine".