644212 has 6 divisors (see below), whose sum is σ = 1127378. Its totient is φ = 322104.

The previous prime is 644201. The next prime is 644227. The reversal of 644212 is 212446.

644212 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 583696 + 60516 = 764^2 + 246^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 644212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80523 + ... + 80530.

2⁶⁴⁴²¹² is an apocalyptic number.

It is an amenable number.

644212 is a deficient number, since it is larger than the sum of its proper divisors (483166).

644212 is a wasteful number, since it uses less digits than its factorization.

644212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161057 (or 161055 counting only the distinct ones).

The product of its digits is 384, while the sum is 19.

The square root of 644212 is about 802.6281829091. The cubic root of 644212 is about 86.3660260230.

Adding to 644212 its reverse (212446), we get a palindrome (856658).

The spelling of 644212 in words is "six hundred forty-four thousand, two hundred twelve".