81948952800 has 1152 divisors, whose sum is σ = 356872158720. Its totient is φ = 17882726400.

The previous prime is 81948952777. The next prime is 81948952853. The reversal of 81948952800 is 825984918.

81948952800 is a `hidden beast` number, since 81 + 9 + 489 + 5 + 2 + 80 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 132818092 + ... + 132818708.

It is an arithmetic number, because the mean of its divisors is an integer number (309784860).

Almost surely, 2^81948952800 is an apocalyptic number.

81948952800 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 81948952800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (178436079360).

81948952800 is an abundant number, since it is smaller than the sum of its proper divisors (274923205920).

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

81948952800 is a wasteful number, since it uses less digits than its factorization.

81948952800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713 (or 694 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 54.

The spelling of 81948952800 in words is "eighty-one billion, nine hundred forty-eight million, nine hundred fifty-two thousand, eight hundred".