6657689 has 4 divisors (see below), whose sum is σ = 6675456. Its totient is φ = 6639924.

The previous prime is 6657671. The next prime is 6657697. The reversal of 6657689 is 9867566.

6657689 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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, and also an emirpimes, since its reverse is a distinct semiprime: 9867566 = 2 ⋅4933783.

It is a cyclic number.

It is not a de Polignac number, because 6657689 - 2¹² = 6653593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6659689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8309 + ... + 9074.

It is an arithmetic number, because the mean of its divisors is an integer number (1668864).

Almost surely, 2^6657689 is an apocalyptic number.

It is an amenable number.

6657689 is a deficient number, since it is larger than the sum of its proper divisors (17767).

6657689 is a wasteful number, since it uses less digits than its factorization.

6657689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17766.

The product of its digits is 544320, while the sum is 47.

The square root of 6657689 is about 2580.2497941091. The cubic root of 6657689 is about 188.1226847469.

The spelling of 6657689 in words is "six million, six hundred fifty-seven thousand, six hundred eighty-nine".