199991567 has 2 divisors, whose sum is σ = 199991568. Its totient is φ = 199991566.

The previous prime is 199991557. The next prime is 199991573. The reversal of 199991567 is 765199991.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 199991567 - 2¹⁶ = 199926031 is a prime.

It is a super-2 number, since 2×199991567² = 79993253742230978, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199991527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99995783 + 99995784.

It is an arithmetic number, because the mean of its divisors is an integer number (99995784).

Almost surely, 2^199991567 is an apocalyptic number.

199991567 is a deficient number, since it is larger than the sum of its proper divisors (1).

199991567 is an equidigital number, since it uses as much as digits as its factorization.

199991567 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1377810, while the sum is 56.

The square root of 199991567 is about 14141.8374690137. The cubic root of 199991567 is about 584.7953281132.

The spelling of 199991567 in words is "one hundred ninety-nine million, nine hundred ninety-one thousand, five hundred sixty-seven".