824538457681 has 3 divisors (see below), whose sum is σ = 824539365723. Its totient is φ = 824537549640.

The previous prime is 824538457643. The next prime is 824538457733. The reversal of 824538457681 is 186754835428.

The square root of 824538457681 is 908041.

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., 78871667281 + 745666790400 = 280841^2 + 863520^2 .

It is not a de Polignac number, because 824538457681 - 2³⁵ = 790178719313 is a prime.

It is a super-2 number, since 2×824538457681² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (824538457781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 454021 + ... + 1362061.

It is an arithmetic number, because the mean of its divisors is an integer number (274846455241).

Almost surely, 2^824538457681 is an apocalyptic number.

824538457681 is the 908041-st square number.

824538457681 is the 454021-st centered octagonal number.

It is an amenable number.

824538457681 is a deficient number, since it is larger than the sum of its proper divisors (908042).

824538457681 is an frugal number, since it uses more digits than its factorization.

824538457681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1816082 (or 908041 counting only the distinct ones).

The product of its digits is 51609600, while the sum is 61.

The spelling of 824538457681 in words is "eight hundred twenty-four billion, five hundred thirty-eight million, four hundred fifty-seven thousand, six hundred eighty-one".