71118521 has 4 divisors (see below), whose sum is σ = 71160192. Its totient is φ = 71076852.

The previous prime is 71118503. The next prime is 71118529. The reversal of 71118521 is 12581117.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 71118521 - 2¹⁴ = 71102137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71118529) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18161 + ... + 21726.

It is an arithmetic number, because the mean of its divisors is an integer number (17790048).

Almost surely, 2^71118521 is an apocalyptic number.

It is an amenable number.

71118521 is a deficient number, since it is larger than the sum of its proper divisors (41671).

71118521 is a wasteful number, since it uses less digits than its factorization.

71118521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41670.

The product of its digits is 560, while the sum is 26.

The square root of 71118521 is about 8433.1797680353. The cubic root of 71118521 is about 414.3120571155.

Adding to 71118521 its reverse (12581117), we get a palindrome (83699638).

The spelling of 71118521 in words is "seventy-one million, one hundred eighteen thousand, five hundred twenty-one".