81739608000 has 224 divisors, whose sum is σ = 281641052160. Its totient is φ = 20849382400.

The previous prime is 81739607923. The next prime is 81739608011. The reversal of 81739608000 is 80693718.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 477961 + ... + 626039.

Almost surely, 2^81739608000 is an apocalyptic number.

81739608000 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 81739608000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140820526080).

81739608000 is an abundant number, since it is smaller than the sum of its proper divisors (199901444160).

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

81739608000 is a wasteful number, since it uses less digits than its factorization.

81739608000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148132 (or 148112 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 42.

The spelling of 81739608000 in words is "eighty-one billion, seven hundred thirty-nine million, six hundred eight thousand".