199962991 has 4 divisors (see below), whose sum is σ = 201831912. Its totient is φ = 198094072.

The previous prime is 199962979. The next prime is 199963003. The reversal of 199962991 is 199269991.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (199962979) and next prime (199963003).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199962991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199962491) 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, 934300 + ... + 934513.

It is an arithmetic number, because the mean of its divisors is an integer number (50457978).

Almost surely, 2^199962991 is an apocalyptic number.

199962991 is a deficient number, since it is larger than the sum of its proper divisors (1868921).

199962991 is a wasteful number, since it uses less digits than its factorization.

199962991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1868920.

The product of its digits is 708588, while the sum is 55.

The square root of 199962991 is about 14140.8270974508. The cubic root of 199962991 is about 584.7674737599.

The spelling of 199962991 in words is "one hundred ninety-nine million, nine hundred sixty-two thousand, nine hundred ninety-one".