648644 has 12 divisors (see below), whose sum is σ = 1171968. Its totient is φ = 313800.

The previous prime is 648631. The next prime is 648649. The reversal of 648644 is 446846.

648644 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 648644.

It is not an unprimeable number, because it can be changed into a prime (648649) by changing a digit.

648644 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, 2492 + ... + 2739.

It is an arithmetic number, because the mean of its divisors is an integer number (97664).

2⁶⁴⁸⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

648644 is a deficient number, since it is larger than the sum of its proper divisors (523324).

648644 is a wasteful number, since it uses less digits than its factorization.

648644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5266 (or 5264 counting only the distinct ones).

The product of its digits is 18432, while the sum is 32.

The square root of 648644 is about 805.3843802806. The cubic root of 648644 is about 86.5636316629.

The spelling of 648644 in words is "six hundred forty-eight thousand, six hundred forty-four".