55211840809 has 2 divisors, whose sum is σ = 55211840810. Its totient is φ = 55211840808.

The previous prime is 55211840777. The next prime is 55211840921. The reversal of 55211840809 is 90804811255.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55211840784 + 25 = 234972^2 + 5^2 .

It is a cyclic number.

It is not a de Polignac number, because 55211840809 - 2⁵ = 55211840777 is a prime.

It is not a weakly prime, because it can be changed into another prime (55211840309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27605920404 + 27605920405.

It is an arithmetic number, because the mean of its divisors is an integer number (27605920405).

Almost surely, 2^55211840809 is an apocalyptic number.

It is an amenable number.

55211840809 is a deficient number, since it is larger than the sum of its proper divisors (1).

55211840809 is an equidigital number, since it uses as much as digits as its factorization.

55211840809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 115200, while the sum is 43.

The spelling of 55211840809 in words is "fifty-five billion, two hundred eleven million, eight hundred forty thousand, eight hundred nine".