71011521 has 12 divisors (see below), whose sum is σ = 117225472. Its totient is φ = 40577976.

The previous prime is 71011489. The next prime is 71011529. The reversal of 71011521 is 12511017.

It is a happy number.

It is not a de Polignac number, because 71011521 - 2⁵ = 71011489 is a prime.

It is a super-2 number, since 2×71011521² = 10085272229466882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 71011494 and 71011503.

It is not an unprimeable number, because it can be changed into a prime (71011529) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 563521 + ... + 563646.

Almost surely, 2^71011521 is an apocalyptic number.

It is an amenable number.

71011521 is a deficient number, since it is larger than the sum of its proper divisors (46213951).

71011521 is a wasteful number, since it uses less digits than its factorization.

71011521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1127180 (or 1127177 counting only the distinct ones).

The product of its (nonzero) digits is 70, while the sum is 18.

The square root of 71011521 is about 8426.8333910194. The cubic root of 71011521 is about 414.1041710837.

Adding to 71011521 its reverse (12511017), we get a palindrome (83522538).

The spelling of 71011521 in words is "seventy-one million, eleven thousand, five hundred twenty-one".