6557009208209 has 2 divisors, whose sum is σ = 6557009208210. Its totient is φ = 6557009208208.

The previous prime is 6557009208157. The next prime is 6557009208241. The reversal of 6557009208209 is 9028029007556.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6388660656400 + 168348551809 = 2527580^2 + 410303^2 .

It is a cyclic number.

It is not a de Polignac number, because 6557009208209 - 2¹² = 6557009204113 is a prime.

It is a super-2 number, since 2×6557009208209² (a number of 26 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6557009208259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3278504604104 + 3278504604105.

It is an arithmetic number, because the mean of its divisors is an integer number (3278504604105).

Almost surely, 2^{6557009208209} is an apocalyptic number.

It is an amenable number.

6557009208209 is a deficient number, since it is larger than the sum of its proper divisors (1).

6557009208209 is an equidigital number, since it uses as much as digits as its factorization.

6557009208209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2721600, while the sum is 53.

The spelling of 6557009208209 in words is "six trillion, five hundred fifty-seven billion, nine million, two hundred eight thousand, two hundred nine".