81102200 has 96 divisors (see below), whose sum is σ = 198082560. Its totient is φ = 30844800.

The previous prime is 81102193. The next prime is 81102239. The reversal of 81102200 is 220118.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 638537 + ... + 638663.

It is an arithmetic number, because the mean of its divisors is an integer number (2063360).

Almost surely, 2^81102200 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81102200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99041280).

81102200 is an abundant number, since it is smaller than the sum of its proper divisors (116980360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81102200 is a wasteful number, since it uses less digits than its factorization.

81102200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277 (or 268 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 81102200 is about 9005.6759879534. The cubic root of 81102200 is about 432.8567673360.

Adding to 81102200 its reverse (220118), we get a palindrome (81322318).

The spelling of 81102200 in words is "eighty-one million, one hundred two thousand, two hundred".