21647302871 has 4 divisors (see below), whose sum is σ = 21737877600. Its totient is φ = 21556728144.

The previous prime is 21647302841. The next prime is 21647302913. The reversal of 21647302871 is 17820374612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21647302871 - 2²⁶ = 21580194007 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21647302811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45287006 + ... + 45287483.

It is an arithmetic number, because the mean of its divisors is an integer number (5434469400).

Almost surely, 2^21647302871 is an apocalyptic number.

21647302871 is a deficient number, since it is larger than the sum of its proper divisors (90574729).

21647302871 is an equidigital number, since it uses as much as digits as its factorization.

21647302871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90574728.

The product of its (nonzero) digits is 112896, while the sum is 41.

The spelling of 21647302871 in words is "twenty-one billion, six hundred forty-seven million, three hundred two thousand, eight hundred seventy-one".