648905 has 8 divisors (see below), whose sum is σ = 783432. Its totient is φ = 515968.

The previous prime is 648889. The next prime is 648911. The reversal of 648905 is 509846.

It can be written as a sum of positive squares in 4 ways, for example, as 4096 + 644809 = 64^2 + 803^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 648905 - 2⁴ = 648889 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 887 + ... + 1443.

It is an arithmetic number, because the mean of its divisors is an integer number (97929).

2⁶⁴⁸⁹⁰⁵ is an apocalyptic number.

It is an amenable number.

648905 is a deficient number, since it is larger than the sum of its proper divisors (134527).

648905 is a wasteful number, since it uses less digits than its factorization.

648905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 795.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 648905 is about 805.5463984154. The cubic root of 648905 is about 86.5752405363.

The spelling of 648905 in words is "six hundred forty-eight thousand, nine hundred five".