648891 has 10 divisors (see below), whose sum is σ = 969452. Its totient is φ = 432540.

The previous prime is 648889. The next prime is 648911. The reversal of 648891 is 198846.

It is a happy number.

648891 is a `hidden beast` number, since 648 + 8 + 9 + 1 = 666.

It is not a de Polignac number, because 648891 - 2¹ = 648889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 3925 + ... + 4086.

2⁶⁴⁸⁸⁹¹ is an apocalyptic number.

648891 is a deficient number, since it is larger than the sum of its proper divisors (320561).

648891 is an equidigital number, since it uses as much as digits as its factorization.

648891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8023 (or 8014 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 648891 is about 805.5377086146. The cubic root of 648891 is about 86.5746179171.

The spelling of 648891 in words is "six hundred forty-eight thousand, eight hundred ninety-one".