55508209 has 2 divisors, whose sum is σ = 55508210. Its totient is φ = 55508208.

The previous prime is 55508171. The next prime is 55508239. The reversal of 55508209 is 90280555.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31888609 + 23619600 = 5647^2 + 4860^2 .

It is a cyclic number.

It is not a de Polignac number, because 55508209 - 2¹⁷ = 55377137 is a prime.

It is a super-2 number, since 2×55508209² = 6162322532775362, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (55508239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27754104 + 27754105.

It is an arithmetic number, because the mean of its divisors is an integer number (27754105).

Almost surely, 2^55508209 is an apocalyptic number.

It is an amenable number.

55508209 is a deficient number, since it is larger than the sum of its proper divisors (1).

55508209 is an equidigital number, since it uses as much as digits as its factorization.

55508209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18000, while the sum is 34.

The square root of 55508209 is about 7450.3831445101. The cubic root of 55508209 is about 381.4629868237.

The spelling of 55508209 in words is "fifty-five million, five hundred eight thousand, two hundred nine".