641061239569 has 3 divisors (see below), whose sum is σ = 641062040233. Its totient is φ = 641060438906.

The previous prime is 641061239551. The next prime is 641061239573. The reversal of 641061239569 is 965932160146.

It is a happy number.

The square root of 641061239569 is 800663.

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, and also an emirpimes, since its reverse is a distinct semiprime: 965932160146 = 2 ⋅482966080073.

It is not a de Polignac number, because 641061239569 - 2⁵ = 641061239537 is a prime.

It is a super-2 number, since 2×641061239569² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (641061239669) 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, 400332 + ... + 1200994.

Almost surely, 2^641061239569 is an apocalyptic number.

641061239569 is the 800663-rd square number.

641061239569 is the 400332-nd centered octagonal number.

It is an amenable number.

641061239569 is a deficient number, since it is larger than the sum of its proper divisors (800664).

641061239569 is an frugal number, since it uses more digits than its factorization.

641061239569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1601326 (or 800663 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 52.

The spelling of 641061239569 in words is "six hundred forty-one billion, sixty-one million, two hundred thirty-nine thousand, five hundred sixty-nine".