3643961 has 2 divisors, whose sum is σ = 3643962. Its totient is φ = 3643960.

The previous prime is 3643951. The next prime is 3643963. The reversal of 3643961 is 1693463.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3534400 + 109561 = 1880^2 + 331^2 .

It is a cyclic number.

It is not a de Polignac number, because 3643961 - 2⁶ = 3643897 is a prime.

Together with 3643963, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (3643963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1821980 + 1821981.

It is an arithmetic number, because the mean of its divisors is an integer number (1821981).

Almost surely, 2^3643961 is an apocalyptic number.

It is an amenable number.

3643961 is a deficient number, since it is larger than the sum of its proper divisors (1).

3643961 is an equidigital number, since it uses as much as digits as its factorization.

3643961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11664, while the sum is 32.

The square root of 3643961 is about 1908.9161846451. The cubic root of 3643961 is about 153.8832110540.

The spelling of 3643961 in words is "three million, six hundred forty-three thousand, nine hundred sixty-one".