81603619608 has 192 divisors, whose sum is σ = 242217423360. Its totient is φ = 22835414784.

The previous prime is 81603619549. The next prime is 81603619663. The reversal of 81603619608 is 80691630618.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 68747191 + ... + 68748377.

It is an arithmetic number, because the mean of its divisors is an integer number (1261549080).

Almost surely, 2^81603619608 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 81603619608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121108711680).

81603619608 is an abundant number, since it is smaller than the sum of its proper divisors (160613803752).

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

81603619608 is a wasteful number, since it uses less digits than its factorization.

81603619608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2366 (or 2355 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 48.

The spelling of 81603619608 in words is "eighty-one billion, six hundred three million, six hundred nineteen thousand, six hundred eight".