9911521331 has 4 divisors (see below), whose sum is σ = 9911861232. Its totient is φ = 9911181432.

The previous prime is 9911521303. The next prime is 9911521349. The reversal of 9911521331 is 1331251199.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 9911521331 - 2¹⁴ = 9911504947 is a prime.

It is a super-2 number, since 2×9911521331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 9911521291 and 9911521300.

It is not an unprimeable number, because it can be changed into a prime (9911521391) 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, 121631 + ... + 186056.

It is an arithmetic number, because the mean of its divisors is an integer number (2477965308).

Almost surely, 2^9911521331 is an apocalyptic number.

9911521331 is a deficient number, since it is larger than the sum of its proper divisors (339901).

9911521331 is a wasteful number, since it uses less digits than its factorization.

9911521331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339900.

The product of its digits is 7290, while the sum is 35.

The square root of 9911521331 is about 99556.6237424713. The cubic root of 9911521331 is about 2148.0618069776.

The spelling of 9911521331 in words is "nine billion, nine hundred eleven million, five hundred twenty-one thousand, three hundred thirty-one".