71165521 has 8 divisors (see below), whose sum is σ = 81384704. Its totient is φ = 60959520.

The previous prime is 71165503. The next prime is 71165527. The reversal of 71165521 is 12556117.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 71165521 - 2¹¹ = 71163473 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 71165521.

It is not an unprimeable number, because it can be changed into a prime (71165527) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15256 + ... + 19366.

It is an arithmetic number, because the mean of its divisors is an integer number (10173088).

Almost surely, 2^71165521 is an apocalyptic number.

It is an amenable number.

71165521 is a deficient number, since it is larger than the sum of its proper divisors (10219183).

71165521 is a wasteful number, since it uses less digits than its factorization.

71165521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6591.

The product of its digits is 2100, while the sum is 28.

The square root of 71165521 is about 8435.9659197984. The cubic root of 71165521 is about 414.4033056321.

The spelling of 71165521 in words is "seventy-one million, one hundred sixty-five thousand, five hundred twenty-one".