644220622006223 has 2 divisors, whose sum is σ = 644220622006224. Its totient is φ = 644220622006222.

The previous prime is 644220622006201. The next prime is 644220622006249. The reversal of 644220622006223 is 322600226022446.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 644220622006223 - 2⁴⁰ = 643121110378447 is a prime.

It is a super-2 number, since 2×644220622006223² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (644220622006523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322110311003111 + 322110311003112.

It is an arithmetic number, because the mean of its divisors is an integer number (322110311003112).

Almost surely, 2^{644220622006223} is an apocalyptic number.

644220622006223 is a deficient number, since it is larger than the sum of its proper divisors (1).

644220622006223 is an equidigital number, since it uses as much as digits as its factorization.

644220622006223 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 663552, while the sum is 41.

Adding to 644220622006223 its reverse (322600226022446), we get a palindrome (966820848028669).

The spelling of 644220622006223 in words is "six hundred forty-four trillion, two hundred twenty billion, six hundred twenty-two million, six thousand, two hundred twenty-three".