21422415121 has 4 divisors (see below), whose sum is σ = 21680516592. Its totient is φ = 21164313652.

The previous prime is 21422415061. The next prime is 21422415137. The reversal of 21422415121 is 12151422412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21422415121 - 2¹⁵ = 21422382353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21422415191) 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, 129050611 + ... + 129050776.

It is an arithmetic number, because the mean of its divisors is an integer number (5420129148).

Almost surely, 2^21422415121 is an apocalyptic number.

It is an amenable number.

21422415121 is a deficient number, since it is larger than the sum of its proper divisors (258101471).

21422415121 is an equidigital number, since it uses as much as digits as its factorization.

21422415121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258101470.

The product of its digits is 1280, while the sum is 25.

Adding to 21422415121 its reverse (12151422412), we get a palindrome (33573837533).

The spelling of 21422415121 in words is "twenty-one billion, four hundred twenty-two million, four hundred fifteen thousand, one hundred twenty-one".