81184212894720 has 704 divisors, whose sum is σ = 287334483980544. Its totient is φ = 19437579141120.

The previous prime is 81184212894713. The next prime is 81184212894787. The reversal of 81184212894720 is 2749821248118.

It is a super-2 number, since 2×81184212894720² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2069264224 + ... + 2069303456.

It is an arithmetic number, because the mean of its divisors is an integer number (408145573836).

Almost surely, 2^{81184212894720} is an apocalyptic number.

81184212894720 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 81184212894720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143667241990272).

81184212894720 is an abundant number, since it is smaller than the sum of its proper divisors (206150271085824).

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

81184212894720 is a wasteful number, since it uses less digits than its factorization.

81184212894720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39558 (or 39540 counting only the distinct ones).

The product of its (nonzero) digits is 4128768, while the sum is 57.

The spelling of 81184212894720 in words is "eighty-one trillion, one hundred eighty-four billion, two hundred twelve million, eight hundred ninety-four thousand, seven hundred twenty".