71897680 has 80 divisors (see below), whose sum is σ = 176131584. Its totient is φ = 27256320.

The previous prime is 71897669. The next prime is 71897681. The reversal of 71897680 is 8679817.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 71897680.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71897681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 131167 + ... + 131713.

Almost surely, 2^71897680 is an apocalyptic number.

71897680 is the 4240-th decagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71897680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88065792).

71897680 is an abundant number, since it is smaller than the sum of its proper divisors (104233904).

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

71897680 is a wasteful number, since it uses less digits than its factorization.

71897680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 644 (or 638 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 46.

The square root of 71897680 is about 8479.2499668308. The cubic root of 71897680 is about 415.8196025022.

The spelling of 71897680 in words is "seventy-one million, eight hundred ninety-seven thousand, six hundred eighty".