648666 has 12 divisors (see below), whose sum is σ = 1405482. Its totient is φ = 216216.

The previous prime is 648653. The next prime is 648671. The reversal of 648666 is 666846.

It can be written as a sum of positive squares in only one way, i.e., 632025 + 16641 = 795^2 + 129^2 .

648666 is a modest number, since divided by 666 gives 648 as remainder.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 648666.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 18001 + ... + 18036.

2⁶⁴⁸⁶⁶⁶ is an apocalyptic number.

648666 is an abundant number, since it is smaller than the sum of its proper divisors (756816).

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

648666 is a wasteful number, since it uses less digits than its factorization.

648666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36045 (or 36042 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

The square root of 648666 is about 805.3980382395. The cubic root of 648666 is about 86.5646103088.

The spelling of 648666 in words is "six hundred forty-eight thousand, six hundred sixty-six".