16663305557 has 2 divisors, whose sum is σ = 16663305558. Its totient is φ = 16663305556.

The previous prime is 16663305541. The next prime is 16663305583. The reversal of 16663305557 is 75550336661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12581884561 + 4081420996 = 112169^2 + 63886^2 .

It is an emirp because it is prime and its reverse (75550336661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16663305557 - 2⁴ = 16663305541 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16663305517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8331652778 + 8331652779.

It is an arithmetic number, because the mean of its divisors is an integer number (8331652779).

Almost surely, 2^16663305557 is an apocalyptic number.

It is an amenable number.

16663305557 is a deficient number, since it is larger than the sum of its proper divisors (1).

16663305557 is an equidigital number, since it uses as much as digits as its factorization.

16663305557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1701000, while the sum is 47.

The spelling of 16663305557 in words is "sixteen billion, six hundred sixty-three million, three hundred five thousand, five hundred fifty-seven".