199987297 has 2 divisors, whose sum is σ = 199987298. Its totient is φ = 199987296.

The previous prime is 199987261. The next prime is 199987301. The reversal of 199987297 is 792789991.

199987297 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., 199826496 + 160801 = 14136^2 + 401^2 .

It is a cyclic number.

It is not a de Polignac number, because 199987297 - 2¹⁵ = 199954529 is a prime.

It is a super-2 number, since 2×199987297² = 79989837922732418, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (199987237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99993648 + 99993649.

It is an arithmetic number, because the mean of its divisors is an integer number (99993649).

Almost surely, 2^199987297 is an apocalyptic number.

It is an amenable number.

199987297 is a deficient number, since it is larger than the sum of its proper divisors (1).

199987297 is an equidigital number, since it uses as much as digits as its factorization.

199987297 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5143824, while the sum is 61.

The square root of 199987297 is about 14141.6864977272. The cubic root of 199987297 is about 584.7911661147.

The spelling of 199987297 in words is "one hundred ninety-nine million, nine hundred eighty-seven thousand, two hundred ninety-seven".