11111111 is nontrivially palindromic in base 10.
11111111 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-11111111 is a prime.
11111111 is a strobogrammatic number because it is the same when read upside-down.
It is a Duffinian number.
11111111 is a nontrivial repdigit in base 10.
It is a plaindrome in base 10.
It is a nialpdrome in base 10.
It is a zygodrome in base 10.
It is a congruent number.
Almost surely, 211111111 is an apocalyptic number.
11111111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.
11111111 is a wasteful number, since it uses less digits than its factorization.
11111111 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 322.
The square root of 11111111 is about 3333.3333166667. Note that the first 4 decimals coincide. The cubic root of 11111111 is about 223.1443159502.
The spelling of 11111111 in words is "eleven million, one hundred eleven thousand, one hundred eleven".