198200021 has 2 divisors, whose sum is σ = 198200022. Its totient is φ = 198200020.

The previous prime is 198200017. The next prime is 198200047. The reversal of 198200021 is 120002891.

198200021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 114276100 + 83923921 = 10690^2 + 9161^2 .

It is a cyclic number.

It is not a de Polignac number, because 198200021 - 2² = 198200017 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 198200021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198200921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99100010 + 99100011.

It is an arithmetic number, because the mean of its divisors is an integer number (99100011).

Almost surely, 2^198200021 is an apocalyptic number.

It is an amenable number.

198200021 is a deficient number, since it is larger than the sum of its proper divisors (1).

198200021 is an equidigital number, since it uses as much as digits as its factorization.

198200021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 198200021 is about 14078.3529221284. The cubic root of 198200021 is about 583.0438678845.

The spelling of 198200021 in words is "one hundred ninety-eight million, two hundred thousand, twenty-one".