199989281 has 2 divisors, whose sum is σ = 199989282. Its totient is φ = 199989280.

The previous prime is 199989263. The next prime is 199989287. The reversal of 199989281 is 182989991.

199989281 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., 118701025 + 81288256 = 10895^2 + 9016^2 .

It is a cyclic number.

It is not a de Polignac number, because 199989281 - 2²⁶ = 132880417 is a prime.

It is a super-2 number, since 2×199989281² = 79991425029793922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (199989287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99994640 + 99994641.

It is an arithmetic number, because the mean of its divisors is an integer number (99994641).

Almost surely, 2^199989281 is an apocalyptic number.

It is an amenable number.

199989281 is a deficient number, since it is larger than the sum of its proper divisors (1).

199989281 is an equidigital number, since it uses as much as digits as its factorization.

199989281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 839808, while the sum is 56.

The square root of 199989281 is about 14141.7566447737. The cubic root of 199989281 is about 584.7930999405.

The spelling of 199989281 in words is "one hundred ninety-nine million, nine hundred eighty-nine thousand, two hundred eighty-one".