11011111001001 has 24 divisors (see below), whose sum is σ = 16413450348960. Its totient is φ = 7295704973208.

The previous prime is 11011111000987. The next prime is 11011111001053. The reversal of 11011111001001 is 10010011111011.

It is not a de Polignac number, because 11011111001001 - 2¹³ = 11011110992809 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (11011111005001) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6957351 + ... + 8392076.

It is an arithmetic number, because the mean of its divisors is an integer number (683893764540).

Almost surely, 2^{11011111001001} is an apocalyptic number.

It is an amenable number.

11011111001001 is a deficient number, since it is larger than the sum of its proper divisors (5402339347959).

11011111001001 is an equidigital number, since it uses as much as digits as its factorization.

11011111001001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15349762 (or 15349593 counting only the distinct ones).

The product of its (nonzero) digits is 1, while the sum is 9.

Adding to 11011111001001 its reverse (10010011111011), we get a palindrome (21021122112012).

The spelling of 11011111001001 in words is "eleven trillion, eleven billion, one hundred eleven million, one thousand, one".