644248 has 16 divisors (see below), whose sum is σ = 1317960. Its totient is φ = 292800.

The previous prime is 644239. The next prime is 644257. The reversal of 644248 is 842446.

It is an interprime number because it is at equal distance from previous prime (644239) and next prime (644257).

It is a congruent number.

It is an unprimeable number.

644248 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3573 + ... + 3748.

2⁶⁴⁴²⁴⁸ is an apocalyptic number.

It is an amenable number.

644248 is an abundant number, since it is smaller than the sum of its proper divisors (673712).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644248 is a wasteful number, since it uses less digits than its factorization.

644248 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7338 (or 7334 counting only the distinct ones).

The product of its digits is 6144, while the sum is 28.

The square root of 644248 is about 802.6506089202. The cubic root of 644248 is about 86.3676347683.

The spelling of 644248 in words is "six hundred forty-four thousand, two hundred forty-eight".