648909 has 6 divisors (see below), whose sum is σ = 937326. Its totient is φ = 432600.

The previous prime is 648889. The next prime is 648911. The reversal of 648909 is 909846.

648909 is a `hidden beast` number, since 648 + 9 + 0 + 9 = 666.

648909 is digitally balanced in base 7, 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., 459684 + 189225 = 678^2 + 435^2 .

It is not a de Polignac number, because 648909 - 2⁸ = 648653 is a prime.

It is an Ulam number.

648909 is strictly pandigital in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648509) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36042 + ... + 36059.

It is an arithmetic number, because the mean of its divisors is an integer number (156221).

2⁶⁴⁸⁹⁰⁹ is an apocalyptic number.

It is an amenable number.

648909 is a deficient number, since it is larger than the sum of its proper divisors (288417).

648909 is a wasteful number, since it uses less digits than its factorization.

648909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72107 (or 72104 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 648909 is about 805.5488811984. The cubic root of 648909 is about 86.5754184259.

The spelling of 648909 in words is "six hundred forty-eight thousand, nine hundred nine".