6643427736 has 32 divisors (see below), whose sum is σ = 18118440000. Its totient is φ = 2013159840.

The previous prime is 6643427731. The next prime is 6643427783. The reversal of 6643427736 is 6377243466.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6643427731) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12581986 + ... + 12582513.

It is an arithmetic number, because the mean of its divisors is an integer number (566201250).

Almost surely, 2^6643427736 is an apocalyptic number.

6643427736 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

6643427736 is an abundant number, since it is smaller than the sum of its proper divisors (11475012264).

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

6643427736 is a wasteful number, since it uses less digits than its factorization.

6643427736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25164519 (or 25164515 counting only the distinct ones).

The product of its digits is 3048192, while the sum is 48.

The square root of 6643427736 is about 81507.2250539791. The cubic root of 6643427736 is about 1879.8826447041.

The spelling of 6643427736 in words is "six billion, six hundred forty-three million, four hundred twenty-seven thousand, seven hundred thirty-six".