991606199 has 8 divisors (see below), whose sum is σ = 1035589632. Its totient is φ = 947695320.

The previous prime is 991606171. The next prime is 991606211.

991606199 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 991606199 - 2⁸ = 991605943 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 (991606169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10802 + ... + 45824.

It is an arithmetic number, because the mean of its divisors is an integer number (129448704).

Almost surely, 2^991606199 is an apocalyptic number.

991606199 is a deficient number, since it is larger than the sum of its proper divisors (43983433).

991606199 is a wasteful number, since it uses less digits than its factorization.

991606199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36277.

The product of its (nonzero) digits is 236196, while the sum is 50.

The square root of 991606199 is about 31489.7792783627. The cubic root of 991606199 is about 997.1942011893.

The spelling of 991606199 in words is "nine hundred ninety-one million, six hundred six thousand, one hundred ninety-nine".