6688748257 has 4 divisors (see below), whose sum is σ = 6739807536. Its totient is φ = 6637688980.

The previous prime is 6688748207. The next prime is 6688748281. The reversal of 6688748257 is 7528478866.

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 6688748257 - 2²³ = 6680359649 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6688748195 and 6688748204.

It is not an unprimeable number, because it can be changed into a prime (6688748207) 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, 25529443 + ... + 25529704.

It is an arithmetic number, because the mean of its divisors is an integer number (1684951884).

Almost surely, 2^6688748257 is an apocalyptic number.

It is an amenable number.

6688748257 is a deficient number, since it is larger than the sum of its proper divisors (51059279).

6688748257 is a wasteful number, since it uses less digits than its factorization.

6688748257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51059278.

The product of its digits is 36126720, while the sum is 61.

The square root of 6688748257 is about 81784.7678788660. The cubic root of 6688748257 is about 1884.1477249523.

The spelling of 6688748257 in words is "six billion, six hundred eighty-eight million, seven hundred forty-eight thousand, two hundred fifty-seven".