43159261681 has 8 divisors (see below), whose sum is σ = 43334982504. Its totient is φ = 42983888640.

The previous prime is 43159261669. The next prime is 43159261709. The reversal of 43159261681 is 18616295134.

It can be written as a sum of positive squares in 4 ways, for example, as 345030625 + 42814231056 = 18575^2 + 206916^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 43159261681 - 2⁹ = 43159261169 is a prime.

It is a super-2 number, since 2×43159261681² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43159261181) 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, 163215 + ... + 336091.

It is an arithmetic number, because the mean of its divisors is an integer number (5416872813).

Almost surely, 2^43159261681 is an apocalyptic number.

It is an amenable number.

43159261681 is a deficient number, since it is larger than the sum of its proper divisors (175720823).

43159261681 is a wasteful number, since it uses less digits than its factorization.

43159261681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173891.

The product of its digits is 311040, while the sum is 46.

The spelling of 43159261681 in words is "forty-three billion, one hundred fifty-nine million, two hundred sixty-one thousand, six hundred eighty-one".