21341421 has 16 divisors (see below), whose sum is σ = 32155200. Its totient is φ = 13985424.

The previous prime is 21341407. The next prime is 21341479. The reversal of 21341421 is 12414312.

It is not a de Polignac number, because 21341421 - 2¹⁴ = 21325037 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21341394 and 21341403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21341491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5106 + ... + 8291.

It is an arithmetic number, because the mean of its divisors is an integer number (2009700).

Almost surely, 2^21341421 is an apocalyptic number.

It is an amenable number.

21341421 is a deficient number, since it is larger than the sum of its proper divisors (10813779).

21341421 is a wasteful number, since it uses less digits than its factorization.

21341421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13465 (or 13459 counting only the distinct ones).

The product of its digits is 192, while the sum is 18.

The square root of 21341421 is about 4619.6775861525. The cubic root of 21341421 is about 277.3795532801.

Adding to 21341421 its reverse (12414312), we get a palindrome (33755733).

The spelling of 21341421 in words is "twenty-one million, three hundred forty-one thousand, four hundred twenty-one".