2643685571 has 2 divisors, whose sum is σ = 2643685572. Its totient is φ = 2643685570.

The previous prime is 2643685543. The next prime is 2643685579. The reversal of 2643685571 is 1755863462.

2643685571 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 is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2643685571 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (2643685579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1321842785 + 1321842786.

It is an arithmetic number, because the mean of its divisors is an integer number (1321842786).

Almost surely, 2^2643685571 is an apocalyptic number.

2643685571 is a deficient number, since it is larger than the sum of its proper divisors (1).

2643685571 is an equidigital number, since it uses as much as digits as its factorization.

2643685571 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1209600, while the sum is 47.

The square root of 2643685571 is about 51416.7829701548. The cubic root of 2643685571 is about 1382.7274998585.

The spelling of 2643685571 in words is "two billion, six hundred forty-three million, six hundred eighty-five thousand, five hundred seventy-one".