16798021 has 2 divisors, whose sum is σ = 16798022. Its totient is φ = 16798020.

The previous prime is 16798009. The next prime is 16798049. The reversal of 16798021 is 12089761.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9235521 + 7562500 = 3039^2 + 2750^2 .

It is an emirp because it is prime and its reverse (12089761) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16798021 - 2²³ = 8409413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16798081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8399010 + 8399011.

It is an arithmetic number, because the mean of its divisors is an integer number (8399011).

Almost surely, 2^16798021 is an apocalyptic number.

It is an amenable number.

16798021 is a deficient number, since it is larger than the sum of its proper divisors (1).

16798021 is an equidigital number, since it uses as much as digits as its factorization.

16798021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 16798021 is about 4098.5388859934. The cubic root of 16798021 is about 256.1057759908.

The spelling of 16798021 in words is "sixteen million, seven hundred ninety-eight thousand, twenty-one".