81832227840 has 1056 divisors, whose sum is σ = 337980988800. Its totient is φ = 18084003840.

The previous prime is 81832227839. The next prime is 81832227853. The reversal of 81832227840 is 4872223818.

81832227840 is a `hidden beast` number, since 8 + 18 + 322 + 278 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (1056).

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 pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 279290734 + ... + 279291026.

Almost surely, 2^81832227840 is an apocalyptic number.

81832227840 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 81832227840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (168990494400).

81832227840 is an abundant number, since it is smaller than the sum of its proper divisors (256148760960).

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

81832227840 is a wasteful number, since it uses less digits than its factorization.

81832227840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383 (or 362 counting only the distinct ones).

The product of its (nonzero) digits is 344064, while the sum is 45.

The spelling of 81832227840 in words is "eighty-one billion, eight hundred thirty-two million, two hundred twenty-seven thousand, eight hundred forty".