81089426880 has 672 divisors, whose sum is σ = 349586385408. Its totient is φ = 16760217600.

The previous prime is 81089426863. The next prime is 81089426893. The reversal of 81089426880 is 8862498018.

It is a tau number, because it is divible by the number of its divisors (672).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 46790494 + ... + 46792226.

Almost surely, 2^81089426880 is an apocalyptic number.

81089426880 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 81089426880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (174793192704).

81089426880 is an abundant number, since it is smaller than the sum of its proper divisors (268496958528).

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

81089426880 is a wasteful number, since it uses less digits than its factorization.

81089426880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1985 (or 1972 counting only the distinct ones).

The product of its (nonzero) digits is 1769472, while the sum is 54.

The spelling of 81089426880 in words is "eighty-one billion, eighty-nine million, four hundred twenty-six thousand, eight hundred eighty".