Adding to 11011101111111 its reverse (11111110111011), we get a palindrome (22122211222122).
It is a semiprime because it is the product of two primes.
It is a Duffinian number.
It is a congruent number.
Almost surely, 211011101111111 is an apocalyptic number.
11011101111111 is an equidigital number, since it uses as much as digits as its factorization.
11011101111111 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 3670367037040.
The spelling of 11011101111111 in words is "eleven trillion, eleven billion, one hundred one million, one hundred eleven thousand, one hundred eleven".