648405 has 20 divisors (see below), whose sum is σ = 1163052. Its totient is φ = 345600.

The previous prime is 648391. The next prime is 648433. The reversal of 648405 is 504846.

It can be written as a sum of positive squares in 2 ways, for example, as 505521 + 142884 = 711^2 + 378^2 .

It is not a de Polignac number, because 648405 - 2⁶ = 648341 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 648405.

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 19 ways as a sum of consecutive naturals, for example, 396 + ... + 1205.

2⁶⁴⁸⁴⁰⁵ is an apocalyptic number.

It is an amenable number.

648405 is a deficient number, since it is larger than the sum of its proper divisors (514647).

648405 is a wasteful number, since it uses less digits than its factorization.

648405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1618 (or 1609 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 648405 is about 805.2359902538. The cubic root of 648405 is about 86.5529985835.

The spelling of 648405 in words is "six hundred forty-eight thousand, four hundred five".