9815939641600 has 81 divisors (see below), whose sum is σ = 24296604750453. Its totient is φ = 3926275599360.

The previous prime is 9815939641597. The next prime is 9815939641601. The reversal of 9815939641600 is 61469395189.

The square root of 9815939641600 is 3133040.

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., 3533738270976 + 6282201370624 = 1879824^2 + 2506432^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9815939641601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 250623619 + ... + 250662781.

Almost surely, 2^{9815939641600} is an apocalyptic number.

9815939641600 is the 3133040-th square number.

It is an amenable number.

9815939641600 is an abundant number, since it is smaller than the sum of its proper divisors (14480665108853).

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

9815939641600 is an frugal number, since it uses more digits than its factorization.

9815939641600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78352 (or 39170 counting only the distinct ones).

The product of its (nonzero) digits is 12597120, while the sum is 61.

The spelling of 9815939641600 in words is "nine trillion, eight hundred fifteen billion, nine hundred thirty-nine million, six hundred forty-one thousand, six hundred".