991000000200 has 576 divisors, whose sum is σ = 3743947872000. Its totient is φ = 215920373760.

The previous prime is 991000000181. The next prime is 991000000201. The reversal of 991000000200 is 2000000199.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (991000000201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 67348044 + ... + 67362756.

It is an arithmetic number, because the mean of its divisors is an integer number (6499909500).

Almost surely, 2^991000000200 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991000000200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1871973936000).

991000000200 is an abundant number, since it is smaller than the sum of its proper divisors (2752947871800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

991000000200 is a wasteful number, since it uses less digits than its factorization.

991000000200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14854 (or 14838 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 21.

Adding to 991000000200 its reverse (2000000199), we get a palindrome (993000000399).

The spelling of 991000000200 in words is "nine hundred ninety-one billion, two hundred", and thus it is an aban number.