81105600 has 168 divisors, whose sum is σ = 271432528. Its totient is φ = 21196800.

The previous prime is 81105581. The next prime is 81105601. The reversal of 81105600 is 650118.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81105601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 292662 + ... + 292938.

Almost surely, 2^81105600 is an apocalyptic number.

81105600 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81105600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135716264).

81105600 is an abundant number, since it is smaller than the sum of its proper divisors (190326928).

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

81105600 is a wasteful number, since it uses less digits than its factorization.

81105600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363 (or 348 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 81105600 is about 9005.8647558133. The cubic root of 81105600 is about 432.8628160517.

Adding to 81105600 its reverse (650118), we get a palindrome (81755718).

The spelling of 81105600 in words is "eighty-one million, one hundred five thousand, six hundred".