9955666665599 has 2 divisors, whose sum is σ = 9955666665600. Its totient is φ = 9955666665598.

The previous prime is 9955666665547. The next prime is 9955666665649.

9955666665599 is nontrivially palindromic in base 10.

It is a strong prime.

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 9955666665599 - 2¹⁶ = 9955666600063 is a prime.

It is a super-2 number, since 2×9955666665599² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a zygodrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 9955666665599.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9955666665509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4977833332799 + 4977833332800.

It is an arithmetic number, because the mean of its divisors is an integer number (4977833332800).

Almost surely, 2^{9955666665599} is an apocalyptic number.

9955666665599 is a deficient number, since it is larger than the sum of its proper divisors (1).

9955666665599 is an equidigital number, since it uses as much as digits as its factorization.

9955666665599 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31886460000, while the sum is 86.

The spelling of 9955666665599 in words is "nine trillion, nine hundred fifty-five billion, six hundred sixty-six million, six hundred sixty-five thousand, five hundred ninety-nine".