16556666416403 has 2 divisors, whose sum is σ = 16556666416404. Its totient is φ = 16556666416402.

The previous prime is 16556666416399. The next prime is 16556666416417. The reversal of 16556666416403 is 30461466665561.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16556666416403 - 2² = 16556666416399 is a prime.

It is not a weakly prime, because it can be changed into another prime (16556668416403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8278333208201 + 8278333208202.

It is an arithmetic number, because the mean of its divisors is an integer number (8278333208202).

Almost surely, 2^{16556666416403} is an apocalyptic number.

16556666416403 is a deficient number, since it is larger than the sum of its proper divisors (1).

16556666416403 is an equidigital number, since it uses as much as digits as its factorization.

16556666416403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 55987200, while the sum is 59.

The spelling of 16556666416403 in words is "sixteen trillion, five hundred fifty-six billion, six hundred sixty-six million, four hundred sixteen thousand, four hundred three".