11111001001000 has 128 divisors (see below), whose sum is σ = 26427072672000. Its totient is φ = 4371939360000.

The previous prime is 11111001000991. The next prime is 11111001001003. The reversal of 11111001001000 is 10010011111.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (11111001001003) 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 31 ways as a sum of consecutive naturals, for example, 14784325 + ... + 15517675.

It is an arithmetic number, because the mean of its divisors is an integer number (206461505250).

Almost surely, 2^{11111001001000} is an apocalyptic number.

11111001001000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11111001001000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13213536336000).

11111001001000 is an abundant number, since it is smaller than the sum of its proper divisors (15316071671000).

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

11111001001000 is a wasteful number, since it uses less digits than its factorization.

11111001001000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 733620 (or 733606 counting only the distinct ones).

The product of its (nonzero) digits is 1, while the sum is 7.

Adding to 11111001001000 its reverse (10010011111), we get a palindrome (11121011012111).

The spelling of 11111001001000 in words is "eleven trillion, one hundred eleven billion, one million, one thousand".