6671666 has 4 divisors (see below), whose sum is σ = 10007502. Its totient is φ = 3335832.

The previous prime is 6671663. The next prime is 6671669. The reversal of 6671666 is 6661766.

It is a happy number.

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

It is an interprime number because it is at equal distance from previous prime (6671663) and next prime (6671669).

It can be written as a sum of positive squares in only one way, i.e., 6528025 + 143641 = 2555^2 + 379^2 .

It is a super-2 number, since 2×6671666² = 89022254431112, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (6671663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1667915 + ... + 1667918.

Almost surely, 2^6671666 is an apocalyptic number.

6671666 is a deficient number, since it is larger than the sum of its proper divisors (3335836).

6671666 is a wasteful number, since it uses less digits than its factorization.

6671666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3335835.

The product of its digits is 54432, while the sum is 38.

The square root of 6671666 is about 2582.9568327791. The cubic root of 6671666 is about 188.2542395492.

It can be divided in two parts, 6671 and 666, that added together give a palindrome (7337).

The spelling of 6671666 in words is "six million, six hundred seventy-one thousand, six hundred sixty-six".