644337 has 6 divisors (see below), whose sum is σ = 930722. Its totient is φ = 429552.

The previous prime is 644327. The next prime is 644341. The reversal of 644337 is 733446.

644337 is nontrivially palindromic in base 15.

It can be written as a sum of positive squares in only one way, i.e., 531441 + 112896 = 729^2 + 336^2 .

It is not a de Polignac number, because 644337 - 2¹⁴ = 627953 is a prime.

It is an Ulam number.

It is a Duffinian number.

644337 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 644337.

It is not an unprimeable number, because it can be changed into a prime (644327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35788 + ... + 35805.

2⁶⁴⁴³³⁷ is an apocalyptic number.

It is an amenable number.

644337 is a deficient number, since it is larger than the sum of its proper divisors (286385).

644337 is a wasteful number, since it uses less digits than its factorization.

644337 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71599 (or 71596 counting only the distinct ones).

The product of its digits is 6048, while the sum is 27.

The square root of 644337 is about 802.7060483141. The cubic root of 644337 is about 86.3716116869.

The spelling of 644337 in words is "six hundred forty-four thousand, three hundred thirty-seven".