648889 has 2 divisors, whose sum is σ = 648890. Its totient is φ = 648888.

The previous prime is 648887. The next prime is 648911. The reversal of 648889 is 988846.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 577600 + 71289 = 760^2 + 267^2 .

It is a cyclic number.

It is not a de Polignac number, because 648889 - 2¹ = 648887 is a prime.

Together with 648887, it forms a pair of twin primes.

648889 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (648887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324444 + 324445.

It is an arithmetic number, because the mean of its divisors is an integer number (324445).

2⁶⁴⁸⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

648889 is a deficient number, since it is larger than the sum of its proper divisors (1).

648889 is an equidigital number, since it uses as much as digits as its factorization.

648889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 110592, while the sum is 43.

The square root of 648889 is about 805.5364672068. The cubic root of 648889 is about 86.5745289708.

Subtracting from 648889 its sum of digits (43), we obtain a palindrome (648846).

The spelling of 648889 in words is "six hundred forty-eight thousand, eight hundred eighty-nine".