21420322271 has 2 divisors, whose sum is σ = 21420322272. Its totient is φ = 21420322270.

The previous prime is 21420322267. The next prime is 21420322291. The reversal of 21420322271 is 17222302412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21420322271 - 2² = 21420322267 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21420322271.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21420322241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10710161135 + 10710161136.

It is an arithmetic number, because the mean of its divisors is an integer number (10710161136).

Almost surely, 2^21420322271 is an apocalyptic number.

21420322271 is a deficient number, since it is larger than the sum of its proper divisors (1).

21420322271 is an equidigital number, since it uses as much as digits as its factorization.

21420322271 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 26.

Adding to 21420322271 its reverse (17222302412), we get a palindrome (38642624683).

The spelling of 21420322271 in words is "twenty-one billion, four hundred twenty million, three hundred twenty-two thousand, two hundred seventy-one".