6647318649 has 24 divisors (see below), whose sum is σ = 9877696160. Its totient is φ = 4418163360.

The previous prime is 6647318647. The next prime is 6647318651. The reversal of 6647318649 is 9468137466.

It is an interprime number because it is at equal distance from previous prime (6647318647) and next prime (6647318651).

It is not a de Polignac number, because 6647318649 - 2¹ = 6647318647 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6647318595 and 6647318604.

It is not an unprimeable number, because it can be changed into a prime (6647318641) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7328454 + ... + 7329360.

Almost surely, 2^6647318649 is an apocalyptic number.

It is an amenable number.

6647318649 is a deficient number, since it is larger than the sum of its proper divisors (3230377511).

6647318649 is an frugal number, since it uses more digits than its factorization.

6647318649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1958 (or 1431 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 54.

The square root of 6647318649 is about 81531.0900761176. The cubic root of 6647318649 is about 1880.2495753811.

It can be divided in two parts, 664731 and 8649, that added together give a triangular number (673380 = T₁₁₆₀).

The spelling of 6647318649 in words is "six billion, six hundred forty-seven million, three hundred eighteen thousand, six hundred forty-nine".