67438412561 has 8 divisors (see below), whose sum is σ = 72628791144. Its totient is φ = 62248435200.

The previous prime is 67438412549. The next prime is 67438412593. The reversal of 67438412561 is 16521483476.

It can be written as a sum of positive squares in 4 ways, for example, as 1469572225 + 65968840336 = 38335^2 + 256844^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-67438412561 is a prime.

It is not an unprimeable number, because it can be changed into a prime (67438412501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 311411 + ... + 481511.

It is an arithmetic number, because the mean of its divisors is an integer number (9078598893).

Almost surely, 2^67438412561 is an apocalyptic number.

It is an amenable number.

67438412561 is a deficient number, since it is larger than the sum of its proper divisors (5190378583).

67438412561 is a wasteful number, since it uses less digits than its factorization.

67438412561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200611.

The product of its digits is 967680, while the sum is 47.

The spelling of 67438412561 in words is "sixty-seven billion, four hundred thirty-eight million, four hundred twelve thousand, five hundred sixty-one".