71091680 has 96 divisors (see below), whose sum is σ = 189278208. Its totient is φ = 24998400.

The previous prime is 71091677. The next prime is 71091719. The reversal of 71091680 is 8619017.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53909 + ... + 55211.

It is an arithmetic number, because the mean of its divisors is an integer number (1971648).

Almost surely, 2^71091680 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 71091680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94639104).

71091680 is an abundant number, since it is smaller than the sum of its proper divisors (118186528).

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

71091680 is a wasteful number, since it uses less digits than its factorization.

71091680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1360 (or 1352 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 32.

The square root of 71091680 is about 8431.5882252397. The cubic root of 71091680 is about 414.2599284104.

The spelling of 71091680 in words is "seventy-one million, ninety-one thousand, six hundred eighty".