6649945 has 8 divisors (see below), whose sum is σ = 7998336. Its totient is φ = 5307696.

The previous prime is 6649919. The next prime is 6649999. The reversal of 6649945 is 5499466.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6649945 - 2¹³ = 6641753 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1344 + ... + 3886.

It is an arithmetic number, because the mean of its divisors is an integer number (999792).

Almost surely, 2^6649945 is an apocalyptic number.

It is an amenable number.

6649945 is a deficient number, since it is larger than the sum of its proper divisors (1348391).

6649945 is a wasteful number, since it uses less digits than its factorization.

6649945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3071.

The product of its digits is 233280, while the sum is 43.

The square root of 6649945 is about 2578.7487275809. The cubic root of 6649945 is about 188.0497171211.

It can be divided in two parts, 664 and 9945, that added together give a square (10609 = 103²).

The spelling of 6649945 in words is "six million, six hundred forty-nine thousand, nine hundred forty-five".