199021 has 2 divisors, whose sum is σ = 199022. Its totient is φ = 199020.

The previous prime is 198997. The next prime is 199033. The reversal of 199021 is 120991.

199021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 114921 + 84100 = 339^2 + 290^2 .

It is a cyclic number.

It is not a de Polignac number, because 199021 - 2¹³ = 190829 is a prime.

It is a nialpdrome in base 12.

It is a junction number, because it is equal to n+sod(n) for n = 198983 and 199001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99510 + 99511.

It is an arithmetic number, because the mean of its divisors is an integer number (99511).

2¹⁹⁹⁰²¹ is an apocalyptic number.

It is an amenable number.

199021 is a deficient number, since it is larger than the sum of its proper divisors (1).

199021 is an equidigital number, since it uses as much as digits as its factorization.

199021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 162, while the sum is 22.

The square root of 199021 is about 446.1176974746. The cubic root of 199021 is about 58.3847781996.

The spelling of 199021 in words is "one hundred ninety-nine thousand, twenty-one".