16683421 has 2 divisors, whose sum is σ = 16683422. Its totient is φ = 16683420.

The previous prime is 16683397. The next prime is 16683427. The reversal of 16683421 is 12438661.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12880921 + 3802500 = 3589^2 + 1950^2 .

It is a cyclic number.

It is not a de Polignac number, because 16683421 - 2⁵ = 16683389 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 (16683427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8341710 + 8341711.

It is an arithmetic number, because the mean of its divisors is an integer number (8341711).

Almost surely, 2^16683421 is an apocalyptic number.

It is an amenable number.

16683421 is a deficient number, since it is larger than the sum of its proper divisors (1).

16683421 is an equidigital number, since it uses as much as digits as its factorization.

16683421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 31.

The square root of 16683421 is about 4084.5343675871. The cubic root of 16683421 is about 255.5220421571.

The spelling of 16683421 in words is "sixteen million, six hundred eighty-three thousand, four hundred twenty-one".