644741052211 has 2 divisors, whose sum is σ = 644741052212. Its totient is φ = 644741052210.

The previous prime is 644741052071. The next prime is 644741052299. The reversal of 644741052211 is 112250147446.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 644741052211 - 2³⁹ = 94985238323 is a prime.

It is a super-2 number, since 2×644741052211² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (644741052611) 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 as a sum of consecutive naturals, namely, 322370526105 + 322370526106.

It is an arithmetic number, because the mean of its divisors is an integer number (322370526106).

Almost surely, 2^644741052211 is an apocalyptic number.

644741052211 is a deficient number, since it is larger than the sum of its proper divisors (1).

644741052211 is an equidigital number, since it uses as much as digits as its factorization.

644741052211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 53760, while the sum is 37.

Adding to 644741052211 its reverse (112250147446), we get a palindrome (756991199657).

The spelling of 644741052211 in words is "six hundred forty-four billion, seven hundred forty-one million, fifty-two thousand, two hundred eleven".