199109549 has 2 divisors, whose sum is σ = 199109550. Its totient is φ = 199109548.

The previous prime is 199109527. The next prime is 199109557. The reversal of 199109549 is 945901991.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 156625225 + 42484324 = 12515^2 + 6518^2 .

It is a cyclic number.

It is not a de Polignac number, because 199109549 - 2⁸ = 199109293 is a prime.

It is a super-2 number, since 2×199109549² = 79289225005966802, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199109579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99554774 + 99554775.

It is an arithmetic number, because the mean of its divisors is an integer number (99554775).

Almost surely, 2^199109549 is an apocalyptic number.

It is an amenable number.

199109549 is a deficient number, since it is larger than the sum of its proper divisors (1).

199109549 is an equidigital number, since it uses as much as digits as its factorization.

199109549 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 131220, while the sum is 47.

The square root of 199109549 is about 14110.6183067929. The cubic root of 199109549 is about 583.9343582395.

The spelling of 199109549 in words is "one hundred ninety-nine million, one hundred nine thousand, five hundred forty-nine".