9999945228361 has 27 divisors (see below), whose sum is σ = 11151422235079. Its totient is φ = 8960605438400.

The previous prime is 9999945228293. The next prime is 9999945228373. The reversal of 9999945228361 is 1638225499999.

The square root of 9999945228361 is 3162269.

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., 2442284453961 + 7557660774400 = 1562781^2 + 2749120^2 .

It is not a de Polignac number, because 9999945228361 - 2⁹ = 9999945227849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9999945228391) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2469730065 + ... + 2469734113.

Almost surely, 2^{9999945228361} is an apocalyptic number.

9999945228361 is the 3162269-th square number.

9999945228361 is the 1581135-th centered octagonal number.

It is an amenable number.

9999945228361 is a deficient number, since it is larger than the sum of its proper divisors (1151477006718).

9999945228361 is an frugal number, since it uses more digits than its factorization.

9999945228361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8262 (or 4131 counting only the distinct ones).

The product of its digits is 680244480, while the sum is 76.

The spelling of 9999945228361 in words is "nine trillion, nine hundred ninety-nine billion, nine hundred forty-five million, two hundred twenty-eight thousand, three hundred sixty-one".