71981688 has 32 divisors (see below), whose sum is σ = 180282960. Its totient is φ = 23950080.

The previous prime is 71981677. The next prime is 71981713. The reversal of 71981688 is 88618917.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12378 + ... + 17238.

Almost surely, 2^71981688 is an apocalyptic number.

It is an amenable number.

71981688 is an abundant number, since it is smaller than the sum of its proper divisors (108301272).

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

71981688 is a wasteful number, since it uses less digits than its factorization.

71981688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5487 (or 5483 counting only the distinct ones).

The product of its digits is 193536, while the sum is 48.

The square root of 71981688 is about 8484.2022606725. The cubic root of 71981688 is about 415.9814926431.

The spelling of 71981688 in words is "seventy-one million, nine hundred eighty-one thousand, six hundred eighty-eight".