6666857 has 4 divisors (see below), whose sum is σ = 6714960. Its totient is φ = 6618756.

The previous prime is 6666841. The next prime is 6666883. The reversal of 6666857 is 7586666.

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: 7586666 = 2 ⋅3793333.

It is a cyclic number.

It is not a de Polignac number, because 6666857 - 2⁴ = 6666841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6666157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23843 + ... + 24120.

It is an arithmetic number, because the mean of its divisors is an integer number (1678740).

Almost surely, 2^6666857 is an apocalyptic number.

It is an amenable number.

6666857 is a deficient number, since it is larger than the sum of its proper divisors (48103).

6666857 is a wasteful number, since it uses less digits than its factorization.

6666857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48102.

The product of its digits is 362880, while the sum is 44.

The square root of 6666857 is about 2582.0257551001. The cubic root of 6666857 is about 188.2089968644.

The spelling of 6666857 in words is "six million, six hundred sixty-six thousand, eight hundred fifty-seven".