3661666 has 4 divisors (see below), whose sum is σ = 5492502. Its totient is φ = 1830832.

The previous prime is 3661649. The next prime is 3661673. The reversal of 3661666 is 6661663.

It is a happy number.

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., 2387025 + 1274641 = 1545^2 + 1129^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 915415 + ... + 915418.

Almost surely, 2^3661666 is an apocalyptic number.

3661666 is a deficient number, since it is larger than the sum of its proper divisors (1830836).

3661666 is a wasteful number, since it uses less digits than its factorization.

3661666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1830835.

The product of its digits is 23328, while the sum is 34.

The square root of 3661666 is about 1913.5480135079. The cubic root of 3661666 is about 154.1320338405.

The spelling of 3661666 in words is "three million, six hundred sixty-one thousand, six hundred sixty-six".