6649645 has 16 divisors (see below), whose sum is σ = 8491392. Its totient is φ = 4987840.

The previous prime is 6649633. The next prime is 6649661. The reversal of 6649645 is 5469466.

It is a de Polignac number, because none of the positive numbers 2^k-6649645 is a prime.

It is a super-3 number, since 3×6649645³ (a number of 21 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6649598 and 6649607.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5550 + ... + 6640.

It is an arithmetic number, because the mean of its divisors is an integer number (530712).

Almost surely, 2^6649645 is an apocalyptic number.

It is an amenable number.

6649645 is a deficient number, since it is larger than the sum of its proper divisors (1841747).

6649645 is a wasteful number, since it uses less digits than its factorization.

6649645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1172.

The product of its digits is 155520, while the sum is 40.

The square root of 6649645 is about 2578.6905591792. The cubic root of 6649645 is about 188.0468892399.

The spelling of 6649645 in words is "six million, six hundred forty-nine thousand, six hundred forty-five".