8971521 has 16 divisors (see below), whose sum is σ = 12936000. Its totient is φ = 5497920.

The previous prime is 8971511. The next prime is 8971559. The reversal of 8971521 is 1251798.

It is not a de Polignac number, because 8971521 - 2¹⁰ = 8970497 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (8971511) 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, 17730 + ... + 18228.

It is an arithmetic number, because the mean of its divisors is an integer number (808500).

Almost surely, 2^8971521 is an apocalyptic number.

It is an amenable number.

8971521 is a deficient number, since it is larger than the sum of its proper divisors (3964479).

8971521 is a wasteful number, since it uses less digits than its factorization.

8971521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 976.

The product of its digits is 5040, while the sum is 33.

The square root of 8971521 is about 2995.2497391703. The cubic root of 8971521 is about 207.7887478572.

The spelling of 8971521 in words is "eight million, nine hundred seventy-one thousand, five hundred twenty-one".