68381841809 has 4 divisors (see below), whose sum is σ = 68382574260. Its totient is φ = 68381109360.

The previous prime is 68381841793. The next prime is 68381841887. The reversal of 68381841809 is 90814818386.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 54602603584 + 13779238225 = 233672^2 + 117385^2 .

It is a cyclic number.

It is not a de Polignac number, because 68381841809 - 2⁴ = 68381841793 is a prime.

It is a super-2 number, since 2×68381841809² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (68381844809) 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 3 ways as a sum of consecutive naturals, for example, 201482 + ... + 421139.

It is an arithmetic number, because the mean of its divisors is an integer number (17095643565).

Almost surely, 2^68381841809 is an apocalyptic number.

It is an amenable number.

68381841809 is a deficient number, since it is larger than the sum of its proper divisors (732451).

68381841809 is a wasteful number, since it uses less digits than its factorization.

68381841809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 732450.

The product of its (nonzero) digits is 2654208, while the sum is 56.

The spelling of 68381841809 in words is "sixty-eight billion, three hundred eighty-one million, eight hundred forty-one thousand, eight hundred nine".