689682081841 has 27 divisors (see below), whose sum is σ = 736467350913. Its totient is φ = 645774249600.

The previous prime is 689682081839. The next prime is 689682081853. The reversal of 689682081841 is 148180286986.

The square root of 689682081841 is 830471.

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

It can be written as a sum of positive squares in 4 ways, for example, as 415085121441 + 274596960400 = 644271^2 + 524020^2 .

It is not a de Polignac number, because 689682081841 - 2¹ = 689682081839 is a prime.

It is a super-2 number, since 2×689682081841² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 689682081841.

It is not an unprimeable number, because it can be changed into a prime (689682081871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1719905241 + ... + 1719905641.

Almost surely, 2^689682081841 is an apocalyptic number.

689682081841 is the 830471-st square number.

689682081841 is the 415236-th centered octagonal number.

It is an amenable number.

689682081841 is a deficient number, since it is larger than the sum of its proper divisors (46785269072).

689682081841 is an frugal number, since it uses more digits than its factorization.

689682081841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1058 (or 529 counting only the distinct ones).

The product of its (nonzero) digits is 10616832, while the sum is 61.

The spelling of 689682081841 in words is "six hundred eighty-nine billion, six hundred eighty-two million, eighty-one thousand, eight hundred forty-one".