Adding to 21110012 its reverse (21001112), we get a palindrome (42111124).
Subtracting from 21110012 its reverse (21001112), we obtain a square (108900 = 3302).
It is a congruent number.
It is an unprimeable number.
Almost surely, 221110012 is an apocalyptic number.
21110012 is a gapful number since it is divisible by the number (22) formed by its first and last digit.
It is an amenable number.
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
21110012 is a wasteful number, since it uses less digits than its factorization.
21110012 is an evil number, because the sum of its binary digits is even.
The square root of 21110012 is about 4594.5633089555. The cubic root of 21110012 is about 276.3733482721.
The spelling of 21110012 in words is "twenty-one million, one hundred ten thousand, twelve".