71681688 has 144 divisors (see below), whose sum is σ = 216679320. Its totient is φ = 21385728.

The previous prime is 71681683. The next prime is 71681689. The reversal of 71681688 is 88618617.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71681681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 523156 + ... + 523292.

Almost surely, 2^71681688 is an apocalyptic number.

71681688 is a gapful number since it is divisible by the number (78) 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 71681688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108339660).

71681688 is an abundant number, since it is smaller than the sum of its proper divisors (144997632).

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

71681688 is a wasteful number, since it uses less digits than its factorization.

71681688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218 (or 198 counting only the distinct ones).

The product of its digits is 129024, while the sum is 45.

The square root of 71681688 is about 8466.5038829496. The cubic root of 71681688 is about 415.4027888852.

The spelling of 71681688 in words is "seventy-one million, six hundred eighty-one thousand, six hundred eighty-eight".