199066921 has 2 divisors, whose sum is σ = 199066922. Its totient is φ = 199066920.

The previous prime is 199066883. The next prime is 199066927. The reversal of 199066921 is 129660991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 147744025 + 51322896 = 12155^2 + 7164^2 .

It is a cyclic number.

It is not a de Polignac number, because 199066921 - 2⁷ = 199066793 is a prime.

It is not a weakly prime, because it can be changed into another prime (199066927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99533460 + 99533461.

It is an arithmetic number, because the mean of its divisors is an integer number (99533461).

Almost surely, 2^199066921 is an apocalyptic number.

It is an amenable number.

199066921 is a deficient number, since it is larger than the sum of its proper divisors (1).

199066921 is an equidigital number, since it uses as much as digits as its factorization.

199066921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52488, while the sum is 43.

The square root of 199066921 is about 14109.1077322416. The cubic root of 199066921 is about 583.8926831406.

The spelling of 199066921 in words is "one hundred ninety-nine million, sixty-six thousand, nine hundred twenty-one".