6666739 has 4 divisors (see below), whose sum is σ = 7017640. Its totient is φ = 6315840.

The previous prime is 6666719. The next prime is 6666749. The reversal of 6666739 is 9376666.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6666739 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6666695 and 6666704.

It is not an unprimeable number, because it can be changed into a prime (6666719) 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, 175422 + ... + 175459.

It is an arithmetic number, because the mean of its divisors is an integer number (1754410).

Almost surely, 2^6666739 is an apocalyptic number.

6666739 is a deficient number, since it is larger than the sum of its proper divisors (350901).

6666739 is a wasteful number, since it uses less digits than its factorization.

6666739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 350900.

The product of its digits is 244944, while the sum is 43.

The square root of 6666739 is about 2582.0029047234. The cubic root of 6666739 is about 188.2078864565.

The spelling of 6666739 in words is "six million, six hundred sixty-six thousand, seven hundred thirty-nine".