11111011111001 has 4 divisors (see below), whose sum is σ = 11244878714832. Its totient is φ = 10977143507172.

The previous prime is 11111011110937. The next prime is 11111011111043. The reversal of 11111011111001 is 10011111011111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 11111011111001 - 2⁶ = 11111011110937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11111011111061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66933801791 + ... + 66933801956.

It is an arithmetic number, because the mean of its divisors is an integer number (2811219678708).

Almost surely, 2^{11111011111001} is an apocalyptic number.

It is an amenable number.

11111011111001 is a deficient number, since it is larger than the sum of its proper divisors (133867603831).

11111011111001 is an equidigital number, since it uses as much as digits as its factorization.

11111011111001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133867603830.

The product of its (nonzero) digits is 1, while the sum is 11.

Adding to 11111011111001 its reverse (10011111011111), we get a palindrome (21122122122112).

The spelling of 11111011111001 in words is "eleven trillion, one hundred eleven billion, eleven million, one hundred eleven thousand, one".