81273600 has 324 divisors, whose sum is σ = 311370696. Its totient is φ = 20152320.

The previous prime is 81273587. The next prime is 81273607. The reversal of 81273600 is 637218.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81273607) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 979159 + ... + 979241.

Almost surely, 2^81273600 is an apocalyptic number.

81273600 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 81273600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (155685348).

81273600 is an abundant number, since it is smaller than the sum of its proper divisors (230097096).

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

81273600 is a wasteful number, since it uses less digits than its factorization.

81273600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132 (or 110 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 81273600 is about 9015.1871860766. The cubic root of 81273600 is about 433.1614834682.

The spelling of 81273600 in words is "eighty-one million, two hundred seventy-three thousand, six hundred".