168505815798441 has 243 divisors, whose sum is σ = 295459493271397. Its totient is φ = 96005243727360.

The previous prime is 168505815798431. The next prime is 168505815798497. The reversal of 168505815798441 is 144897518505861.

The square root of 168505815798441 is 12980979.

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

168505815798441 is a `hidden beast` number, since 1 + 6 + 8 + 5 + 0 + 5 + 8 + 1 + 579 + 8 + 4 + 41 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 87842425360041 + 80663390438400 = 9372429^2 + 8981280^2 .

It is a tau number, because it is divible by the number of its divisors (243).

It is not a de Polignac number, because 168505815798441 - 2⁵ = 168505815798409 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 168505815798441.

It is not an unprimeable number, because it can be changed into a prime (168505815798431) 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 242 ways as a sum of consecutive naturals, for example, 196622888485 + ... + 196622889341.

Almost surely, 2^{168505815798441} is an apocalyptic number.

168505815798441 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

168505815798441 is the 12980979-th square number.

168505815798441 is the 6490490-th centered octagonal number.

It is an amenable number.

168505815798441 is a deficient number, since it is larger than the sum of its proper divisors (126953677472956).

168505815798441 is an frugal number, since it uses more digits than its factorization.

168505815798441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1794 (or 888 counting only the distinct ones).

The product of its (nonzero) digits is 387072000, while the sum is 72.

The spelling of 168505815798441 in words is "one hundred sixty-eight trillion, five hundred five billion, eight hundred fifteen million, seven hundred ninety-eight thousand, four hundred forty-one".