16443988202021 has 2 divisors, whose sum is σ = 16443988202022. Its totient is φ = 16443988202020.

The previous prime is 16443988202011. The next prime is 16443988202023. The reversal of 16443988202021 is 12020288934461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16124521336225 + 319466865796 = 4015535^2 + 565214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16443988202021 is a prime.

It is a super-3 number, since 3×16443988202021³ (a number of 41 digits) contains 333 as substring.

Together with 16443988202023, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16443988202023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8221994101010 + 8221994101011.

It is an arithmetic number, because the mean of its divisors is an integer number (8221994101011).

Almost surely, 2^{16443988202021} is an apocalyptic number.

It is an amenable number.

16443988202021 is a deficient number, since it is larger than the sum of its proper divisors (1).

16443988202021 is an equidigital number, since it uses as much as digits as its factorization.

16443988202021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1327104, while the sum is 50.

The spelling of 16443988202021 in words is "sixteen trillion, four hundred forty-three billion, nine hundred eighty-eight million, two hundred two thousand, twenty-one".