16663693 has 2 divisors, whose sum is σ = 16663694. Its totient is φ = 16663692.

The previous prime is 16663681. The next prime is 16663697. The reversal of 16663693 is 39636661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10323369 + 6340324 = 3213^2 + 2518^2 .

It is an emirp because it is prime and its reverse (39636661) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16663693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16663697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8331846 + 8331847.

It is an arithmetic number, because the mean of its divisors is an integer number (8331847).

Almost surely, 2^16663693 is an apocalyptic number.

It is an amenable number.

16663693 is a deficient number, since it is larger than the sum of its proper divisors (1).

16663693 is an equidigital number, since it uses as much as digits as its factorization.

16663693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 104976, while the sum is 40.

The square root of 16663693 is about 4082.1186900922. The cubic root of 16663693 is about 255.4212849022.

The spelling of 16663693 in words is "sixteen million, six hundred sixty-three thousand, six hundred ninety-three".