3866691643 has 2 divisors, whose sum is σ = 3866691644. Its totient is φ = 3866691642.

The previous prime is 3866691641. The next prime is 3866691727. The reversal of 3866691643 is 3461966683.

3866691643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3866691643 - 2¹ = 3866691641 is a prime.

Together with 3866691641, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (3866691641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1933345821 + 1933345822.

It is an arithmetic number, because the mean of its divisors is an integer number (1933345822).

Almost surely, 2^3866691643 is an apocalyptic number.

3866691643 is a deficient number, since it is larger than the sum of its proper divisors (1).

3866691643 is an equidigital number, since it uses as much as digits as its factorization.

3866691643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3359232, while the sum is 52.

The square root of 3866691643 is about 62182.7278510681. The cubic root of 3866691643 is about 1569.5669546869.

The spelling of 3866691643 in words is "three billion, eight hundred sixty-six million, six hundred ninety-one thousand, six hundred forty-three".