3861997691 has 2 divisors, whose sum is σ = 3861997692. Its totient is φ = 3861997690.

The previous prime is 3861997681. The next prime is 3861997697. The reversal of 3861997691 is 1967991683.

3861997691 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3861997691 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 3861997691.

It is not a weakly prime, because it can be changed into another prime (3861997697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1930998845 + 1930998846.

It is an arithmetic number, because the mean of its divisors is an integer number (1930998846).

Almost surely, 2^3861997691 is an apocalyptic number.

3861997691 is a deficient number, since it is larger than the sum of its proper divisors (1).

3861997691 is an equidigital number, since it uses as much as digits as its factorization.

3861997691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4408992, while the sum is 59.

The square root of 3861997691 is about 62144.9731756318. The cubic root of 3861997691 is about 1568.9315747226.

The spelling of 3861997691 in words is "three billion, eight hundred sixty-one million, nine hundred ninety-seven thousand, six hundred ninety-one".