6666744407 has 4 divisors (see below), whose sum is σ = 6666966216. Its totient is φ = 6666522600.

The previous prime is 6666744341. The next prime is 6666744433. The reversal of 6666744407 is 7044476666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7044476666 = 2 ⋅3522238333.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6666744407 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6666744307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57128 + ... + 128829.

It is an arithmetic number, because the mean of its divisors is an integer number (1666741554).

Almost surely, 2^6666744407 is an apocalyptic number.

6666744407 is a deficient number, since it is larger than the sum of its proper divisors (221809).

6666744407 is a wasteful number, since it uses less digits than its factorization.

6666744407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221808.

The product of its (nonzero) digits is 4064256, while the sum is 50.

The square root of 6666744407 is about 81650.1341517575. The cubic root of 6666744407 is about 1882.0793733791.

The spelling of 6666744407 in words is "six billion, six hundred sixty-six million, seven hundred forty-four thousand, four hundred seven".