641252281 has 2 divisors, whose sum is σ = 641252282. Its totient is φ = 641252280.

The previous prime is 641252279. The next prime is 641252317. The reversal of 641252281 is 182252146.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 635846656 + 5405625 = 25216^2 + 2325^2 .

It is a cyclic number.

It is not a de Polignac number, because 641252281 - 2¹ = 641252279 is a prime.

It is a super-2 number, since 2×641252281² = 822408975775405922, which contains 22 as substring.

Together with 641252279, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (641252881) 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 as a sum of consecutive naturals, namely, 320626140 + 320626141.

It is an arithmetic number, because the mean of its divisors is an integer number (320626141).

Almost surely, 2^641252281 is an apocalyptic number.

It is an amenable number.

641252281 is a deficient number, since it is larger than the sum of its proper divisors (1).

641252281 is an equidigital number, since it uses as much as digits as its factorization.

641252281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7680, while the sum is 31.

The square root of 641252281 is about 25322.9595624208. The cubic root of 641252281 is about 862.3355843149.

The spelling of 641252281 in words is "six hundred forty-one million, two hundred fifty-two thousand, two hundred eighty-one".