Adding to 81007700 its reverse (770018), we get a palindrome (81777718).
It is a congruent number.
It is an unprimeable number.
Almost surely, 281007700 is an apocalyptic number.
It is an amenable number.
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
81007700 is a wasteful number, since it uses less digits than its factorization.
81007700 is an evil number, because the sum of its binary digits is even.
The square root of 81007700 is about 9000.4277676119. The cubic root of 81007700 is about 432.6885809315.
The spelling of 81007700 in words is "eighty-one million, seven thousand, seven hundred".