21022141421 has 2 divisors, whose sum is σ = 21022141422. Its totient is φ = 21022141420.

The previous prime is 21022141403. The next prime is 21022141463. The reversal of 21022141421 is 12414122012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19208574025 + 1813567396 = 138595^2 + 42586^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21022141421 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21022141393 and 21022141402.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21022140421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10511070710 + 10511070711.

It is an arithmetic number, because the mean of its divisors is an integer number (10511070711).

Almost surely, 2^21022141421 is an apocalyptic number.

It is an amenable number.

21022141421 is a deficient number, since it is larger than the sum of its proper divisors (1).

21022141421 is an equidigital number, since it uses as much as digits as its factorization.

21022141421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21022141421 its reverse (12414122012), we get a palindrome (33436263433).

The spelling of 21022141421 in words is "twenty-one billion, twenty-two million, one hundred forty-one thousand, four hundred twenty-one".