16640917 has 2 divisors, whose sum is σ = 16640918. Its totient is φ = 16640916.

The previous prime is 16640879. The next prime is 16640933. The reversal of 16640917 is 71904661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15792676 + 848241 = 3974^2 + 921^2 .

It is an emirp because it is prime and its reverse (71904661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16640917 - 2¹⁵ = 16608149 is a prime.

It is equal to p_1069648 and since 16640917 and 1069648 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16640317) 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, 8320458 + 8320459.

It is an arithmetic number, because the mean of its divisors is an integer number (8320459).

Almost surely, 2^16640917 is an apocalyptic number.

It is an amenable number.

16640917 is a deficient number, since it is larger than the sum of its proper divisors (1).

16640917 is an equidigital number, since it uses as much as digits as its factorization.

16640917 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 16640917 is about 4079.3280083857. The cubic root of 16640917 is about 255.3048615769.

The spelling of 16640917 in words is "sixteen million, six hundred forty thousand, nine hundred seventeen".