6649820 has 24 divisors (see below), whose sum is σ = 14034384. Its totient is φ = 2646656.

The previous prime is 6649801. The next prime is 6649823. The reversal of 6649820 is 289466.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6649823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3947 + ... + 5373.

It is an arithmetic number, because the mean of its divisors is an integer number (584766).

Almost surely, 2^6649820 is an apocalyptic number.

It is an amenable number.

6649820 is an abundant number, since it is smaller than the sum of its proper divisors (7384564).

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

6649820 is a wasteful number, since it uses less digits than its factorization.

6649820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1669 (or 1667 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 6649820 is about 2578.7244909063. The cubic root of 6649820 is about 188.0485388476.

The spelling of 6649820 in words is "six million, six hundred forty-nine thousand, eight hundred twenty".