16628009 has 2 divisors, whose sum is σ = 16628010. Its totient is φ = 16628008.

The previous prime is 16627981. The next prime is 16628039. The reversal of 16628009 is 90082661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16224784 + 403225 = 4028^2 + 635^2 .

It is an emirp because it is prime and its reverse (90082661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16628009 - 2⁸ = 16627753 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (16628039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8314004 + 8314005.

It is an arithmetic number, because the mean of its divisors is an integer number (8314005).

Almost surely, 2^16628009 is an apocalyptic number.

It is an amenable number.

16628009 is a deficient number, since it is larger than the sum of its proper divisors (1).

16628009 is an equidigital number, since it uses as much as digits as its factorization.

16628009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 16628009 is about 4077.7455781351. The cubic root of 16628009 is about 255.2388330122.

The spelling of 16628009 in words is "sixteen million, six hundred twenty-eight thousand, nine".