8165705784381 has 12 divisors (see below), whose sum is σ = 11801152375740. Its totient is φ = 5440922000640.

The previous prime is 8165705784377. The next prime is 8165705784389. The reversal of 8165705784381 is 1834875075618.

8165705784381 is a `hidden beast` number, since 8 + 1 + 6 + 57 + 0 + 578 + 4 + 3 + 8 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 5052919536900 + 3112786247481 = 2247870^2 + 1764309^2 .

It is not a de Polignac number, because 8165705784381 - 2² = 8165705784377 is a prime.

It is a super-2 number, since 2×8165705784381² (a number of 27 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (63) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8165705784389) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 240136690 + ... + 240170691.

It is an arithmetic number, because the mean of its divisors is an integer number (983429364645).

Almost surely, 2^{8165705784381} is an apocalyptic number.

It is an amenable number.

8165705784381 is a deficient number, since it is larger than the sum of its proper divisors (3635446591359).

8165705784381 is a wasteful number, since it uses less digits than its factorization.

8165705784381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 480309276 (or 480309273 counting only the distinct ones).

The product of its (nonzero) digits is 45158400, while the sum is 63.

The spelling of 8165705784381 in words is "eight trillion, one hundred sixty-five billion, seven hundred five million, seven hundred eighty-four thousand, three hundred eighty-one".