16985021 has 2 divisors, whose sum is σ = 16985022. Its totient is φ = 16985020.

The previous prime is 16985011. The next prime is 16985041. The reversal of 16985021 is 12058961.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16924996 + 60025 = 4114^2 + 245^2 .

It is a cyclic number.

It is not a de Polignac number, because 16985021 - 2¹⁰ = 16983997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16985011) 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, 8492510 + 8492511.

It is an arithmetic number, because the mean of its divisors is an integer number (8492511).

Almost surely, 2^16985021 is an apocalyptic number.

It is an amenable number.

16985021 is a deficient number, since it is larger than the sum of its proper divisors (1).

16985021 is an equidigital number, since it uses as much as digits as its factorization.

16985021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 16985021 is about 4121.2887547465. The cubic root of 16985021 is about 257.0526168214.

The spelling of 16985021 in words is "sixteen million, nine hundred eighty-five thousand, twenty-one".