81061200 has 360 divisors, whose sum is σ = 323818560. Its totient is φ = 18585600.

The previous prime is 81061199. The next prime is 81061207. The reversal of 81061200 is 216018.

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81061207) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 910756 + ... + 910844.

It is an arithmetic number, because the mean of its divisors is an integer number (899496).

Almost surely, 2^81061200 is an apocalyptic number.

81061200 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 81061200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (161909280).

81061200 is an abundant number, since it is smaller than the sum of its proper divisors (242757360).

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

81061200 is a wasteful number, since it uses less digits than its factorization.

81061200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147 (or 133 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 81061200 is about 9003.3993580203. The cubic root of 81061200 is about 432.7838136270.

Adding to 81061200 its reverse (216018), we get a palindrome (81277218).

It can be divided in two parts, 8 and 1061200, that added together give a cube (1061208 = 102³).

The spelling of 81061200 in words is "eighty-one million, sixty-one thousand, two hundred".