3666647 has 2 divisors, whose sum is σ = 3666648. Its totient is φ = 3666646.

The previous prime is 3666629. The next prime is 3666659. The reversal of 3666647 is 7466663.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 3666647 - 2⁶ = 3666583 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 3666647.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3666347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1833323 + 1833324.

It is an arithmetic number, because the mean of its divisors is an integer number (1833324).

Almost surely, 2^3666647 is an apocalyptic number.

3666647 is a deficient number, since it is larger than the sum of its proper divisors (1).

3666647 is an equidigital number, since it uses as much as digits as its factorization.

3666647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 38.

The square root of 3666647 is about 1914.8490802149. The cubic root of 3666647 is about 154.2018912775.

The spelling of 3666647 in words is "three million, six hundred sixty-six thousand, six hundred forty-seven".