71681438808 has 1024 divisors, whose sum is σ = 269485056000. Its totient is φ = 17167417344.

The previous prime is 71681438783. The next prime is 71681438809. The reversal of 71681438808 is 80883418617.

It is a happy number.

71681438808 is a `hidden beast` number, since 71 + 68 + 1 + 438 + 80 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71681438809) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 634348960 + ... + 634349072.

It is an arithmetic number, because the mean of its divisors is an integer number (263169000).

Almost surely, 2^71681438808 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 71681438808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134742528000).

71681438808 is an abundant number, since it is smaller than the sum of its proper divisors (197803617192).

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

71681438808 is a wasteful number, since it uses less digits than its factorization.

71681438808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241 (or 231 counting only the distinct ones).

The product of its (nonzero) digits is 2064384, while the sum is 54.

The spelling of 71681438808 in words is "seventy-one billion, six hundred eighty-one million, four hundred thirty-eight thousand, eight hundred eight".