81524195280 has 480 divisors, whose sum is σ = 324918787200. Its totient is φ = 18722119680.

The previous prime is 81524195257. The next prime is 81524195297. The reversal of 81524195280 is 8259142518.

81524195280 is a `hidden beast` number, since 8 + 152 + 419 + 5 + 2 + 80 = 666.

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 95 ways as a sum of consecutive naturals, for example, 4957632 + ... + 4974048.

It is an arithmetic number, because the mean of its divisors is an integer number (676914140).

Almost surely, 2^81524195280 is an apocalyptic number.

81524195280 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 81524195280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162459393600).

81524195280 is an abundant number, since it is smaller than the sum of its proper divisors (243394591920).

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

81524195280 is a wasteful number, since it uses less digits than its factorization.

81524195280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16480 (or 16457 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 45.

The spelling of 81524195280 in words is "eighty-one billion, five hundred twenty-four million, one hundred ninety-five thousand, two hundred eighty".