9823917981969 has 405 divisors, whose sum is σ = 19140296514273. Its totient is φ = 5004469806336.

The previous prime is 9823917981959. The next prime is 9823917981971. The reversal of 9823917981969 is 9691897193289.

The square root of 9823917981969 is 3134313.

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

9823917981969 is a `hidden beast` number, since 9 + 82 + 391 + 7 + 98 + 1 + 9 + 69 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 4294779588225 + 5529138393744 = 2072385^2 + 2351412^2 .

It is not a de Polignac number, because 9823917981969 - 2⁴³ = 1027824959761 is a prime.

It is a super-2 number, since 2×9823917981969² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is not an unprimeable number, because it can be changed into a prime (9823917981959) 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 404 ways as a sum of consecutive naturals, for example, 110381100877 + ... + 110381100965.

Almost surely, 2^{9823917981969} is an apocalyptic number.

9823917981969 is the 3134313-rd square number.

9823917981969 is the 1567157-th centered octagonal number.

It is an amenable number.

9823917981969 is a deficient number, since it is larger than the sum of its proper divisors (9316378532304).

9823917981969 is an equidigital number, since it uses as much as digits as its factorization.

9823917981969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316 (or 155 counting only the distinct ones).

The product of its digits is 952342272, while the sum is 81.

Multiplying 9823917981969 by its sum of digits (81), we get a square (795737356539489 = 28208817²).

9823917981969 divided by its sum of digits (81) gives a square (121282938049 = 348257²).

The spelling of 9823917981969 in words is "nine trillion, eight hundred twenty-three billion, nine hundred seventeen million, nine hundred eighty-one thousand, nine hundred sixty-nine".