641305253 has 8 divisors (see below), whose sum is σ = 649396440. Its totient is φ = 633233920.

The previous prime is 641305237. The next prime is 641305283. The reversal of 641305253 is 352503146.

It can be written as a sum of positive squares in 4 ways, for example, as 186677569 + 454627684 = 13663^2 + 21322^2 .

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 641305253 - 2⁴ = 641305237 is a prime.

It is a super-2 number, since 2×641305253² = 822544855050788018, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641305213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 66413 + ... + 75453.

It is an arithmetic number, because the mean of its divisors is an integer number (81174555).

Almost surely, 2^641305253 is an apocalyptic number.

It is an amenable number.

641305253 is a deficient number, since it is larger than the sum of its proper divisors (8091187).

641305253 is an equidigital number, since it uses as much as digits as its factorization.

641305253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9927.

The product of its (nonzero) digits is 10800, while the sum is 29.

The square root of 641305253 is about 25324.0054691196. The cubic root of 641305253 is about 862.3593286790.

Adding to 641305253 its reverse (352503146), we get a palindrome (993808399).

The spelling of 641305253 in words is "six hundred forty-one million, three hundred five thousand, two hundred fifty-three".