16966321 has 2 divisors, whose sum is σ = 16966322. Its totient is φ = 16966320.

The previous prime is 16966319. The next prime is 16966349. The reversal of 16966321 is 12366961.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12702096 + 4264225 = 3564^2 + 2065^2 .

It is an emirp because it is prime and its reverse (12366961) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16966321 - 2¹ = 16966319 is a prime.

It is a super-4 number, since 4×16966321⁴ (a number of 30 digits) contains 4444 as substring.

Together with 16966319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (16966351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8483160 + 8483161.

It is an arithmetic number, because the mean of its divisors is an integer number (8483161).

Almost surely, 2^16966321 is an apocalyptic number.

It is an amenable number.

16966321 is a deficient number, since it is larger than the sum of its proper divisors (1).

16966321 is an equidigital number, since it uses as much as digits as its factorization.

16966321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11664, while the sum is 34.

The square root of 16966321 is about 4119.0194221441. The cubic root of 16966321 is about 256.9582464329.

The spelling of 16966321 in words is "sixteen million, nine hundred sixty-six thousand, three hundred twenty-one".