6665844485666 has 4 divisors (see below), whose sum is σ = 9998766728502. Its totient is φ = 3332922242832.

The previous prime is 6665844485653. The next prime is 6665844485777.

6665844485666 is nontrivially palindromic in base 10.

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

It can be written as a sum of positive squares in only one way, i.e., 3681329105041 + 2984515380625 = 1918679^2 + 1727575^2 .

It is a junction number, because it is equal to n+sod(n) for n = 6665844485593 and 6665844485602.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1666461121415 + ... + 1666461121418.

Almost surely, 2^{6665844485666} is an apocalyptic number.

6665844485666 is a deficient number, since it is larger than the sum of its proper divisors (3332922242836).

6665844485666 is a wasteful number, since it uses less digits than its factorization.

6665844485666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3332922242835.

The product of its digits is 4777574400, while the sum is 74.

The spelling of 6665844485666 in words is "six trillion, six hundred sixty-five billion, eight hundred forty-four million, four hundred eighty-five thousand, six hundred sixty-six".