644411 has 2 divisors, whose sum is σ = 644412. Its totient is φ = 644410.

The previous prime is 644401. The next prime is 644431. The reversal of 644411 is 114446.

It is a happy number.

It is an a-pointer prime, because the next prime (644431) can be obtained adding 644411 to its sum of digits (20).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 644411 - 2¹⁸ = 382267 is a prime.

It is a Sophie Germain prime.

It is a nialpdrome in base 10.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 644411.

It is not a weakly prime, because it can be changed into another prime (644401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322205 + 322206.

It is an arithmetic number, because the mean of its divisors is an integer number (322206).

2⁶⁴⁴⁴¹¹ is an apocalyptic number.

644411 is a deficient number, since it is larger than the sum of its proper divisors (1).

644411 is an equidigital number, since it uses as much as digits as its factorization.

644411 is an evil number, because the sum of its binary digits is even.

The product of its digits is 384, while the sum is 20.

The square root of 644411 is about 802.7521410747. The cubic root of 644411 is about 86.3749180595.

Adding to 644411 its reverse (114446), we get a palindrome (758857).

The spelling of 644411 in words is "six hundred forty-four thousand, four hundred eleven".