81255746880 has 1344 divisors, whose sum is σ = 369739468800. Its totient is φ = 15879536640.

The previous prime is 81255746837. The next prime is 81255746893. The reversal of 81255746880 is 8864755218.

81255746880 is a `hidden beast` number, since 8 + 1 + 2 + 5 + 574 + 68 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1344).

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, 453942631 + ... + 453942809.

Almost surely, 2^81255746880 is an apocalyptic number.

81255746880 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 81255746880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (184869734400).

81255746880 is an abundant number, since it is smaller than the sum of its proper divisors (288483721920).

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

81255746880 is a wasteful number, since it uses less digits than its factorization.

81255746880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332 (or 319 counting only the distinct ones).

The product of its (nonzero) digits is 4300800, while the sum is 54.

The spelling of 81255746880 in words is "eighty-one billion, two hundred fifty-five million, seven hundred forty-six thousand, eight hundred eighty".