85641716826961 has 3 divisors (see below), whose sum is σ = 85641726081243. Its totient is φ = 85641707572680.

The previous prime is 85641716826947. The next prime is 85641716826971. The reversal of 85641716826961 is 16962861714658.

The square root of 85641716826961 is 9254281.

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

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 only one way, i.e., 44229402969361 + 41412313857600 = 6650519^2 + 6435240^2 .

It is not a de Polignac number, because 85641716826961 - 2²⁵ = 85641683272529 is a prime.

It is a super-2 number, since 2×85641716826961² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85641716826971) 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 2 ways as a sum of consecutive naturals, for example, 4627141 + ... + 13881421.

It is an arithmetic number, because the mean of its divisors is an integer number (28547242027081).

Almost surely, 2^{85641716826961} is an apocalyptic number.

85641716826961 is the 9254281-st square number.

85641716826961 is the 4627141-st centered octagonal number.

It is an amenable number.

85641716826961 is a deficient number, since it is larger than the sum of its proper divisors (9254282).

85641716826961 is an frugal number, since it uses more digits than its factorization.

85641716826961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18508562 (or 9254281 counting only the distinct ones).

The product of its digits is 209018880, while the sum is 70.

The spelling of 85641716826961 in words is "eighty-five trillion, six hundred forty-one billion, seven hundred sixteen million, eight hundred twenty-six thousand, nine hundred sixty-one".