9217921426609 has 9 divisors (see below), whose sum is σ = 10722912912747. Its totient is φ = 7901057291904.

The previous prime is 9217921426589. The next prime is 9217921426613. The reversal of 9217921426609 is 9066241297129.

The square root of 9217921426609 is 3036103.

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

It can be written as a sum of positive squares in only one way, i.e., 1094737412209 + 8123184014400 = 1046297^2 + 2850120^2 .

It is not a de Polignac number, because 9217921426609 - 2¹³ = 9217921418417 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9217921426619) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 21035857 + ... + 21469585.

It is an arithmetic number, because the mean of its divisors is an integer number (1191434768083).

Almost surely, 2^{9217921426609} is an apocalyptic number.

9217921426609 is the 3036103-rd square number.

9217921426609 is the 1518052-nd centered octagonal number.

It is an amenable number.

9217921426609 is a deficient number, since it is larger than the sum of its proper divisors (1504991486138).

9217921426609 is an frugal number, since it uses more digits than its factorization.

9217921426609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 867472 (or 433736 counting only the distinct ones).

The product of its (nonzero) digits is 5878656, while the sum is 58.

The spelling of 9217921426609 in words is "nine trillion, two hundred seventeen billion, nine hundred twenty-one million, four hundred twenty-six thousand, six hundred nine".