3661643 has 2 divisors, whose sum is σ = 3661644. Its totient is φ = 3661642.

The previous prime is 3661633. The next prime is 3661649. The reversal of 3661643 is 3461663.

It is a strong prime.

It is an emirp because it is prime and its reverse (3461663) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3661643 - 2¹⁰ = 3660619 is a prime.

It is not a weakly prime, because it can be changed into another prime (3661649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1830821 + 1830822.

It is an arithmetic number, because the mean of its divisors is an integer number (1830822).

Almost surely, 2^3661643 is an apocalyptic number.

3661643 is a deficient number, since it is larger than the sum of its proper divisors (1).

3661643 is an equidigital number, since it uses as much as digits as its factorization.

3661643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7776, while the sum is 29.

The square root of 3661643 is about 1913.5420037198. The cubic root of 3661643 is about 154.1317111236.

The spelling of 3661643 in words is "three million, six hundred sixty-one thousand, six hundred forty-three".