81372800 has 96 divisors (see below), whose sum is σ = 204897600. Its totient is φ = 31923200.

The previous prime is 81372787. The next prime is 81372803. The reversal of 81372800 is 827318.

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (81372803) 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 11 ways as a sum of consecutive naturals, for example, 188585 + ... + 189015.

It is an arithmetic number, because the mean of its divisors is an integer number (2134350).

Almost surely, 2^81372800 is an apocalyptic number.

81372800 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 81372800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102448800).

81372800 is an abundant number, since it is smaller than the sum of its proper divisors (123524800).

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

81372800 is a wasteful number, since it uses less digits than its factorization.

81372800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 514 (or 497 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 81372800 is about 9020.6873352312. The cubic root of 81372800 is about 433.3376462424.

The spelling of 81372800 in words is "eighty-one million, three hundred seventy-two thousand, eight hundred".