21421414121 has 4 divisors (see below), whose sum is σ = 21421842000. Its totient is φ = 21420986244.

The previous prime is 21421414061. The next prime is 21421414123. The reversal of 21421414121 is 12141412412.

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 a de Polignac number, because none of the positive numbers 2^k-21421414121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21421414123) 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, 127091 + ... + 242888.

It is an arithmetic number, because the mean of its divisors is an integer number (5355460500).

Almost surely, 2^21421414121 is an apocalyptic number.

It is an amenable number.

21421414121 is a deficient number, since it is larger than the sum of its proper divisors (427879).

21421414121 is an equidigital number, since it uses as much as digits as its factorization.

21421414121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427878.

The product of its digits is 512, while the sum is 23.

Adding to 21421414121 its reverse (12141412412), we get a palindrome (33562826533).

The spelling of 21421414121 in words is "twenty-one billion, four hundred twenty-one million, four hundred fourteen thousand, one hundred twenty-one".