20641864571 has 2 divisors, whose sum is σ = 20641864572. Its totient is φ = 20641864570.

The previous prime is 20641864543. The next prime is 20641864589. The reversal of 20641864571 is 17546814602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20641864571 - 2¹⁰ = 20641863547 is a prime.

It is not a weakly prime, because it can be changed into another prime (20641864511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10320932285 + 10320932286.

It is an arithmetic number, because the mean of its divisors is an integer number (10320932286).

Almost surely, 2^20641864571 is an apocalyptic number.

20641864571 is a deficient number, since it is larger than the sum of its proper divisors (1).

20641864571 is an equidigital number, since it uses as much as digits as its factorization.

20641864571 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 322560, while the sum is 44.

The spelling of 20641864571 in words is "twenty billion, six hundred forty-one million, eight hundred sixty-four thousand, five hundred seventy-one".