6649940 has 48 divisors (see below), whose sum is σ = 15410304. Its totient is φ = 2390400.

The previous prime is 6649919. The next prime is 6649999. The reversal of 6649940 is 499466.

It is a junction number, because it is equal to n+sod(n) for n = 6649894 and 6649903.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 36650 + ... + 36830.

It is an arithmetic number, because the mean of its divisors is an integer number (321048).

Almost surely, 2^6649940 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6649940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7705152).

6649940 is an abundant number, since it is smaller than the sum of its proper divisors (8760364).

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

6649940 is a wasteful number, since it uses less digits than its factorization.

6649940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 368 (or 366 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 38.

The square root of 6649940 is about 2578.7477581183. The cubic root of 6649940 is about 188.0496699905.

It can be divided in two parts, 6 and 649940, that added together give a palindrome (649946).

The spelling of 6649940 in words is "six million, six hundred forty-nine thousand, nine hundred forty".