81875259648 has 1728 divisors, whose sum is σ = 344726323200. Its totient is φ = 18632540160.

The previous prime is 81875259619. The next prime is 81875259649. The reversal of 81875259648 is 84695257818.

81875259648 is a `hidden beast` number, since 8 + 18 + 7 + 525 + 96 + 4 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (1728).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (81875259649) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 2641137393 + ... + 2641137423.

It is an arithmetic number, because the mean of its divisors is an integer number (199494400).

Almost surely, 2^81875259648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81875259648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (172363161600).

81875259648 is an abundant number, since it is smaller than the sum of its proper divisors (262851063552).

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

81875259648 is a wasteful number, since it uses less digits than its factorization.

81875259648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125 (or 92 counting only the distinct ones).

The product of its digits is 38707200, while the sum is 63.

The spelling of 81875259648 in words is "eighty-one billion, eight hundred seventy-five million, two hundred fifty-nine thousand, six hundred forty-eight".