991020199 has 8 divisors (see below), whose sum is σ = 1072618400. Its totient is φ = 910188576.

The previous prime is 991020193. The next prime is 991020203.

991020199 is nontrivially palindromic in base 10.

991020199 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 991020199 - 2⁵ = 991020167 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 (991020193) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 188952 + ... + 194125.

It is an arithmetic number, because the mean of its divisors is an integer number (134077300).

Almost surely, 2^991020199 is an apocalyptic number.

991020199 is a deficient number, since it is larger than the sum of its proper divisors (81598201).

991020199 is a wasteful number, since it uses less digits than its factorization.

991020199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383289.

The product of its (nonzero) digits is 13122, while the sum is 40.

The square root of 991020199 is about 31480.4732969503. The cubic root of 991020199 is about 996.9977283856.

The spelling of 991020199 in words is "nine hundred ninety-one million, twenty thousand, one hundred ninety-nine".