3961881641 has 2 divisors, whose sum is σ = 3961881642. Its totient is φ = 3961881640.

The previous prime is 3961881613. The next prime is 3961881689. The reversal of 3961881641 is 1461881693.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3880791616 + 81090025 = 62296^2 + 9005^2 .

It is a cyclic number.

It is not a de Polignac number, because 3961881641 - 2³⁰ = 2888139817 is a prime.

It is a super-2 number, since 2×3961881641² = 31393012274585705762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (3961281641) 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, 1980940820 + 1980940821.

It is an arithmetic number, because the mean of its divisors is an integer number (1980940821).

Almost surely, 2^3961881641 is an apocalyptic number.

It is an amenable number.

3961881641 is a deficient number, since it is larger than the sum of its proper divisors (1).

3961881641 is an equidigital number, since it uses as much as digits as its factorization.

3961881641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 248832, while the sum is 47.

The square root of 3961881641 is about 62943.4797338056. The cubic root of 3961881641 is about 1582.3425222747.

The spelling of 3961881641 in words is "three billion, nine hundred sixty-one million, eight hundred eighty-one thousand, six hundred forty-one".