21289820571 has 10 divisors (see below), whose sum is σ = 31803312332. Its totient is φ = 14193213660.

The previous prime is 21289820569. The next prime is 21289820599. The reversal of 21289820571 is 17502898212.

It is not a de Polignac number, because 21289820571 - 2¹ = 21289820569 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21289820971) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 131418565 + ... + 131418726.

Almost surely, 2^21289820571 is an apocalyptic number.

21289820571 is a deficient number, since it is larger than the sum of its proper divisors (10513491761).

21289820571 is an equidigital number, since it uses as much as digits as its factorization.

21289820571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262837303 (or 262837294 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The spelling of 21289820571 in words is "twenty-one billion, two hundred eighty-nine million, eight hundred twenty thousand, five hundred seventy-one".