644343 has 16 divisors (see below), whose sum is σ = 999936. Its totient is φ = 361440.

The previous prime is 644341. The next prime is 644353. The reversal of 644343 is 343446.

It is not a de Polignac number, because 644343 - 2¹ = 644341 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1030 + ... + 1532.

It is an arithmetic number, because the mean of its divisors is an integer number (62496).

2⁶⁴⁴³⁴³ is an apocalyptic number.

644343 is a deficient number, since it is larger than the sum of its proper divisors (355593).

644343 is a wasteful number, since it uses less digits than its factorization.

644343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 574.

The product of its digits is 3456, while the sum is 24.

The square root of 644343 is about 802.7097856635. The cubic root of 644343 is about 86.3718797806.

Adding to 644343 its reverse (343446), we get a palindrome (987789).

The spelling of 644343 in words is "six hundred forty-four thousand, three hundred forty-three".