9959521 has 16 divisors (see below), whose sum is σ = 11789568. Its totient is φ = 8294400.

The previous prime is 9959513. The next prime is 9959533. The reversal of 9959521 is 1259599.

It is a 4-Lehmer number, since φ(9959521) divides (9959521-1)⁴.

It is a cyclic number.

It is not a de Polignac number, because 9959521 - 2³ = 9959513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9959581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36616 + ... + 36886.

It is an arithmetic number, because the mean of its divisors is an integer number (736848).

Almost surely, 2^9959521 is an apocalyptic number.

It is an amenable number.

9959521 is a deficient number, since it is larger than the sum of its proper divisors (1830047).

9959521 is a wasteful number, since it uses less digits than its factorization.

9959521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 552.

The product of its digits is 36450, while the sum is 40.

The square root of 9959521 is about 3155.8708782205. The cubic root of 9959521 is about 215.1523780074.

The spelling of 9959521 in words is "nine million, nine hundred fifty-nine thousand, five hundred twenty-one".