3666655 has 4 divisors (see below), whose sum is σ = 4399992. Its totient is φ = 2933320.

The previous prime is 3666647. The next prime is 3666659. The reversal of 3666655 is 5566663.

It is a happy number.

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

It is not a de Polignac number, because 3666655 - 2³ = 3666647 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 (3666659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 366661 + ... + 366670.

It is an arithmetic number, because the mean of its divisors is an integer number (1099998).

Almost surely, 2^3666655 is an apocalyptic number.

3666655 is a deficient number, since it is larger than the sum of its proper divisors (733337).

3666655 is an equidigital number, since it uses as much as digits as its factorization.

3666655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 733336.

The product of its digits is 97200, while the sum is 37.

The square root of 3666655 is about 1914.8511691513. The cubic root of 3666655 is about 154.2020034248.

It can be divided in two parts, 366 and 6655, that added together give a triangular number (7021 = T₁₁₈).

The spelling of 3666655 in words is "three million, six hundred sixty-six thousand, six hundred fifty-five".