81817554124800 has 2484 divisors, whose sum is σ = 346444771480080. Its totient is φ = 19079721123840.

The previous prime is 81817554124793. The next prime is 81817554124927. The reversal of 81817554124800 is 842145571818.

81817554124800 is a `hidden beast` number, since 8 + 1 + 8 + 1 + 7 + 554 + 1 + 2 + 4 + 80 + 0 = 666.

It is a super-2 number, since 2×81817554124800² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

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 107 ways as a sum of consecutive naturals, for example, 4306187059191 + ... + 4306187059209.

Almost surely, 2^{81817554124800} is an apocalyptic number.

81817554124800 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 81817554124800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173222385740040).

81817554124800 is an abundant number, since it is smaller than the sum of its proper divisors (264627217355280).

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

81817554124800 is an frugal number, since it uses more digits than its factorization.

81817554124800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114 (or 42 counting only the distinct ones).

The product of its (nonzero) digits is 2867200, while the sum is 54.

The spelling of 81817554124800 in words is "eighty-one trillion, eight hundred seventeen billion, five hundred fifty-four million, one hundred twenty-four thousand, eight hundred".