71978688 has 84 divisors (see below), whose sum is σ = 217205560. Its totient is φ = 22726656.

The previous prime is 71978677. The next prime is 71978693. The reversal of 71978688 is 88687917.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7656 + ... + 14232.

Almost surely, 2^71978688 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 71978688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108602780).

71978688 is an abundant number, since it is smaller than the sum of its proper divisors (145226872).

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

71978688 is a wasteful number, since it uses less digits than its factorization.

71978688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6614 (or 6601 counting only the distinct ones).

The product of its digits is 1354752, while the sum is 54.

The square root of 71978688 is about 8484.0254596506. The cubic root of 71978688 is about 415.9757135723.

The spelling of 71978688 in words is "seventy-one million, nine hundred seventy-eight thousand, six hundred eighty-eight".