199999291 has 4 divisors (see below), whose sum is σ = 201979584. Its totient is φ = 198019000.

The previous prime is 199999279. The next prime is 199999307. The reversal of 199999291 is 192999991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 192999991 = 101 ⋅1910891.

It is a cyclic number.

It is not a de Polignac number, because 199999291 - 2¹¹ = 199997243 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (199999201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 989995 + ... + 990196.

It is an arithmetic number, because the mean of its divisors is an integer number (50494896).

Almost surely, 2^199999291 is an apocalyptic number.

199999291 is a deficient number, since it is larger than the sum of its proper divisors (1980293).

199999291 is a wasteful number, since it uses less digits than its factorization.

199999291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1980292.

The product of its digits is 1062882, while the sum is 58.

The square root of 199999291 is about 14142.1105567733. The cubic root of 199999291 is about 584.8028565989.

The spelling of 199999291 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, two hundred ninety-one".