81730252800 has 1248 divisors, whose sum is σ = 354920616960. Its totient is φ = 18048614400.

The previous prime is 81730252763. The next prime is 81730252829. The reversal of 81730252800 is 825203718.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 793497549 + ... + 793497651.

It is an arithmetic number, because the mean of its divisors is an integer number (284391520).

Almost surely, 2^81730252800 is an apocalyptic number.

81730252800 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 81730252800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (177460308480).

81730252800 is an abundant number, since it is smaller than the sum of its proper divisors (273190364160).

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

81730252800 is a wasteful number, since it uses less digits than its factorization.

81730252800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The spelling of 81730252800 in words is "eighty-one billion, seven hundred thirty million, two hundred fifty-two thousand, eight hundred".