649808 has 20 divisors (see below), whose sum is σ = 1333620. Its totient is φ = 305664.

The previous prime is 649801. The next prime is 649813. The reversal of 649808 is 808946.

It can be written as a sum of positive squares in 2 ways, for example, as 327184 + 322624 = 572^2 + 568^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649801) by changing a digit.

649808 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 923 + ... + 1466.

It is an arithmetic number, because the mean of its divisors is an integer number (66681).

2⁶⁴⁹⁸⁰⁸ is an apocalyptic number.

649808 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

649808 is an abundant number, since it is smaller than the sum of its proper divisors (683812).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

649808 is a wasteful number, since it uses less digits than its factorization.

649808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2414 (or 2408 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 649808 is about 806.1066926902. The cubic root of 649808 is about 86.6153805707.

The spelling of 649808 in words is "six hundred forty-nine thousand, eight hundred eight".