21422871361 has 4 divisors (see below), whose sum is σ = 21423600724. Its totient is φ = 21422142000.

The previous prime is 21422871359. The next prime is 21422871391. The reversal of 21422871361 is 16317822412.

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

It can be written as a sum of positive squares in 2 ways, for example, as 20925358336 + 497513025 = 144656^2 + 22305^2 .

It is a cyclic number.

It is not a de Polignac number, because 21422871361 - 2¹ = 21422871359 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21422871361.

It is not an unprimeable number, because it can be changed into a prime (21422871391) 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, 318690 + ... + 380011.

It is an arithmetic number, because the mean of its divisors is an integer number (5355900181).

Almost surely, 2^21422871361 is an apocalyptic number.

It is an amenable number.

21422871361 is a deficient number, since it is larger than the sum of its proper divisors (729363).

21422871361 is an equidigital number, since it uses as much as digits as its factorization.

21422871361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 729362.

The product of its digits is 32256, while the sum is 37.

The spelling of 21422871361 in words is "twenty-one billion, four hundred twenty-two million, eight hundred seventy-one thousand, three hundred sixty-one".