6647646137 has 4 divisors (see below), whose sum is σ = 7251977616. Its totient is φ = 6043314660.

The previous prime is 6647646079. The next prime is 6647646157. The reversal of 6647646137 is 7316467466.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6647646137 - 2⁶ = 6647646073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6647646157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 302165723 + ... + 302165744.

It is an arithmetic number, because the mean of its divisors is an integer number (1812994404).

Almost surely, 2^6647646137 is an apocalyptic number.

It is an amenable number.

6647646137 is a deficient number, since it is larger than the sum of its proper divisors (604331479).

6647646137 is a wasteful number, since it uses less digits than its factorization.

6647646137 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 604331478.

The product of its digits is 3048192, while the sum is 50.

The square root of 6647646137 is about 81533.0984140797. The cubic root of 6647646137 is about 1880.2804524457.

The spelling of 6647646137 in words is "six billion, six hundred forty-seven million, six hundred forty-six thousand, one hundred thirty-seven".