65557320209 has 2 divisors, whose sum is σ = 65557320210. Its totient is φ = 65557320208.

The previous prime is 65557320161. The next prime is 65557320217. The reversal of 65557320209 is 90202375556.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 33542091025 + 32015229184 = 183145^2 + 178928^2 .

It is a cyclic number.

It is not a de Polignac number, because 65557320209 - 2⁸ = 65557319953 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 65557320209.

It is not a weakly prime, because it can be changed into another prime (65557320299) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32778660104 + 32778660105.

It is an arithmetic number, because the mean of its divisors is an integer number (32778660105).

Almost surely, 2^65557320209 is an apocalyptic number.

It is an amenable number.

65557320209 is a deficient number, since it is larger than the sum of its proper divisors (1).

65557320209 is an equidigital number, since it uses as much as digits as its factorization.

65557320209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 567000, while the sum is 44.

The spelling of 65557320209 in words is "sixty-five billion, five hundred fifty-seven million, three hundred twenty thousand, two hundred nine".