81115932643200 has 8064 divisors, whose sum is σ = 421964922204000. Its totient is φ = 15260050391040.

The previous prime is 81115932643171. The next prime is 81115932643253. The reversal of 81115932643200 is 234623951118.

81115932643200 is a `hidden beast` number, since 8 + 1 + 1 + 1 + 593 + 26 + 4 + 32 + 0 + 0 = 666.

81115932643200 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (8064).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 1007 ways as a sum of consecutive naturals, for example, 4269259612791 + ... + 4269259612809.

Almost surely, 2^{81115932643200} is an apocalyptic number.

81115932643200 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 81115932643200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (210982461102000).

81115932643200 is an abundant number, since it is smaller than the sum of its proper divisors (340848989560800).

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

81115932643200 is a wasteful number, since it uses less digits than its factorization.

81115932643200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 66 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 81115932643200 in words is "eighty-one trillion, one hundred fifteen billion, nine hundred thirty-two million, six hundred forty-three thousand, two hundred".