3643891 has 2 divisors, whose sum is σ = 3643892. Its totient is φ = 3643890.

The previous prime is 3643883. The next prime is 3643897. The reversal of 3643891 is 1983463.

It is a strong prime.

It is an emirp because it is prime and its reverse (1983463) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3643891 - 2³ = 3643883 is a prime.

3643891 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (3643897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1821945 + 1821946.

It is an arithmetic number, because the mean of its divisors is an integer number (1821946).

Almost surely, 2^3643891 is an apocalyptic number.

3643891 is a deficient number, since it is larger than the sum of its proper divisors (1).

3643891 is an equidigital number, since it uses as much as digits as its factorization.

3643891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 34.

The square root of 3643891 is about 1908.8978495456. The cubic root of 3643891 is about 153.8822256891.

The spelling of 3643891 in words is "three million, six hundred forty-three thousand, eight hundred ninety-one".