21886243571 has 2 divisors, whose sum is σ = 21886243572. Its totient is φ = 21886243570.

The previous prime is 21886243541. The next prime is 21886243627. The reversal of 21886243571 is 17534268812.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21886243571 is a prime.

It is not a weakly prime, because it can be changed into another prime (21886243531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10943121785 + 10943121786.

It is an arithmetic number, because the mean of its divisors is an integer number (10943121786).

Almost surely, 2^21886243571 is an apocalyptic number.

21886243571 is a deficient number, since it is larger than the sum of its proper divisors (1).

21886243571 is an equidigital number, since it uses as much as digits as its factorization.

21886243571 is an evil number, because the sum of its binary digits is even.

The product of its digits is 645120, while the sum is 47.

The spelling of 21886243571 in words is "twenty-one billion, eight hundred eighty-six million, two hundred forty-three thousand, five hundred seventy-one".