21899812 is nontrivially palindromic in base 10.
It is an unprimeable number.
Almost surely, 221899812 is an apocalyptic number.
21899812 is a gapful number since it is divisible by the number (22) formed by its first and last digit.
It is an amenable number.
21899812 is a wasteful number, since it uses less digits than its factorization.
21899812 is an evil number, because the sum of its binary digits is even.
The square root of 21899812 is about 4679.7234961053. The cubic root of 21899812 is about 279.7779361759. Note that the first 3 decimals are identical.
The spelling of 21899812 in words is "twenty-one million, eight hundred ninety-nine thousand, eight hundred twelve".