9165217362921 has 135 divisors (see below), whose sum is σ = 14895404319477. Its totient is φ = 5614999729920.

The previous prime is 9165217362919. The next prime is 9165217362929. The reversal of 9165217362921 is 1292637125619.

The square root of 9165217362921 is 3027411.

It is a perfect power (a square), and thus also a powerful number.

9165217362921 is a `hidden beast` number, since 9 + 1 + 6 + 5 + 2 + 1 + 7 + 3 + 629 + 2 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1530849425625 + 7634367937296 = 1237275^2 + 2763036^2 .

It is not a de Polignac number, because 9165217362921 - 2¹ = 9165217362919 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (9165217362929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 21770112291 + ... + 21770112711.

Almost surely, 2^{9165217362921} is an apocalyptic number.

9165217362921 is the 3027411-st square number.

9165217362921 is the 1513706-th centered octagonal number.

It is an amenable number.

9165217362921 is a deficient number, since it is larger than the sum of its proper divisors (5730186956556).

9165217362921 is an frugal number, since it uses more digits than its factorization.

9165217362921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 982 (or 488 counting only the distinct ones).

The product of its digits is 2449440, while the sum is 54.

The spelling of 9165217362921 in words is "nine trillion, one hundred sixty-five billion, two hundred seventeen million, three hundred sixty-two thousand, nine hundred twenty-one".