11111011001001 has 48 divisors (see below), whose sum is σ = 17034654244608. Its totient is φ = 7234008134400.

The previous prime is 11111011000981. The next prime is 11111011001009. The reversal of 11111011001001 is 10010011011111.

It is not a de Polignac number, because 11111011001001 - 2¹⁸ = 11111010738857 is a prime.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (11111011001009) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4209921 + ... + 6320241.

It is an arithmetic number, because the mean of its divisors is an integer number (354888630096).

Almost surely, 2^{11111011001001} is an apocalyptic number.

It is an amenable number.

11111011001001 is a deficient number, since it is larger than the sum of its proper divisors (5923643243607).

11111011001001 is an equidigital number, since it uses as much as digits as its factorization.

11111011001001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2110844 (or 2110832 counting only the distinct ones).

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

Adding to 11111011001001 its reverse (10010011011111), we get a palindrome (21121022012112).

The spelling of 11111011001001 in words is "eleven trillion, one hundred eleven billion, eleven million, one thousand, one".