3945643613 has 2 divisors, whose sum is σ = 3945643614. Its totient is φ = 3945643612.

The previous prime is 3945643571. The next prime is 3945643621. The reversal of 3945643613 is 3163465493.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3431850724 + 513792889 = 58582^2 + 22667^2 .

It is a cyclic number.

It is not a de Polignac number, because 3945643613 - 2¹² = 3945639517 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3945643673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1972821806 + 1972821807.

It is an arithmetic number, because the mean of its divisors is an integer number (1972821807).

Almost surely, 2^3945643613 is an apocalyptic number.

It is an amenable number.

3945643613 is a deficient number, since it is larger than the sum of its proper divisors (1).

3945643613 is an equidigital number, since it uses as much as digits as its factorization.

3945643613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 699840, while the sum is 44.

The square root of 3945643613 is about 62814.3583346992. The cubic root of 3945643613 is about 1580.1777844330.

The spelling of 3945643613 in words is "three billion, nine hundred forty-five million, six hundred forty-three thousand, six hundred thirteen".