16686749 has 2 divisors, whose sum is σ = 16686750. Its totient is φ = 16686748.

The previous prime is 16686743. The next prime is 16686763. The reversal of 16686749 is 94768661.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16662724 + 24025 = 4082^2 + 155^2 .

It is a cyclic number.

It is not a de Polignac number, because 16686749 - 2²⁰ = 15638173 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16686743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8343374 + 8343375.

It is an arithmetic number, because the mean of its divisors is an integer number (8343375).

Almost surely, 2^16686749 is an apocalyptic number.

It is an amenable number.

16686749 is a deficient number, since it is larger than the sum of its proper divisors (1).

16686749 is an equidigital number, since it uses as much as digits as its factorization.

16686749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 47.

The square root of 16686749 is about 4084.9417376506. The cubic root of 16686749 is about 255.5390314948.

The spelling of 16686749 in words is "sixteen million, six hundred eighty-six thousand, seven hundred forty-nine".