9781325216 has 72 divisors (see below), whose sum is σ = 20917079820. Its totient is φ = 4502354688.

The previous prime is 9781325201. The next prime is 9781325227. The reversal of 9781325216 is 6125231879.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 6 ways, for example, as 217267600 + 9564057616 = 14740^2 + 97796^2 .

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 26223206 + ... + 26223578.

Almost surely, 2^9781325216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9781325216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10458539910).

9781325216 is an abundant number, since it is smaller than the sum of its proper divisors (11135754604).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9781325216 is an frugal number, since it uses more digits than its factorization.

9781325216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 795 (or 388 counting only the distinct ones).

The product of its digits is 181440, while the sum is 44.

The square root of 9781325216 is about 98900.5824856457. The cubic root of 9781325216 is about 2138.6147916811.

The spelling of 9781325216 in words is "nine billion, seven hundred eighty-one million, three hundred twenty-five thousand, two hundred sixteen".