4000649 has 2 divisors, whose sum is σ = 4000650. Its totient is φ = 4000648.

The previous prime is 4000631. The next prime is 4000651. The reversal of 4000649 is 9460004.

4000649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3489424 + 511225 = 1868^2 + 715^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4000649 is a prime.

Together with 4000651, 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 (4000669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2000324 + 2000325.

It is an arithmetic number, because the mean of its divisors is an integer number (2000325).

Almost surely, 2^4000649 is an apocalyptic number.

It is an amenable number.

4000649 is a deficient number, since it is larger than the sum of its proper divisors (1).

4000649 is an equidigital number, since it uses as much as digits as its factorization.

4000649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 4000649 is about 2000.1622434193. The cubic root of 4000649 is about 158.7486899266.

The spelling of 4000649 in words is "four million, six hundred forty-nine", and thus it is an aban number.