644220622006201 has 2 divisors, whose sum is σ = 644220622006202. Its totient is φ = 644220622006200.

The previous prime is 644220622006163. The next prime is 644220622006223. The reversal of 644220622006201 is 102600226022446.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 489437040154176 + 154783581852025 = 22123224^2 + 12441205^2 .

It is a cyclic number.

It is not a de Polignac number, because 644220622006201 - 2⁴⁵ = 609036249917369 is a prime.

It is not a weakly prime, because it can be changed into another prime (644220622006001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322110311003100 + 322110311003101.

It is an arithmetic number, because the mean of its divisors is an integer number (322110311003101).

Almost surely, 2^{644220622006201} is an apocalyptic number.

It is an amenable number.

644220622006201 is a deficient number, since it is larger than the sum of its proper divisors (1).

644220622006201 is an equidigital number, since it uses as much as digits as its factorization.

644220622006201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 110592, while the sum is 37.

Adding to 644220622006201 its reverse (102600226022446), we get a palindrome (746820848028647).

The spelling of 644220622006201 in words is "six hundred forty-four trillion, two hundred twenty billion, six hundred twenty-two million, six thousand, two hundred one".