81608242512 has 320 divisors, whose sum is σ = 234499276800. Its totient is φ = 24379729920.

The previous prime is 81608242453. The next prime is 81608242523. The reversal of 81608242512 is 21524280618.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 126132973 + ... + 126133619.

It is an arithmetic number, because the mean of its divisors is an integer number (732810240).

Almost surely, 2^81608242512 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 81608242512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117249638400).

81608242512 is an abundant number, since it is smaller than the sum of its proper divisors (152891034288).

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

81608242512 is a wasteful number, since it uses less digits than its factorization.

81608242512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834 (or 828 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 39.

The spelling of 81608242512 in words is "eighty-one billion, six hundred eight million, two hundred forty-two thousand, five hundred twelve".