21344121 has 8 divisors (see below), whose sum is σ = 31620960. Its totient is φ = 14229396.

The previous prime is 21344119. The next prime is 21344131. The reversal of 21344121 is 12144312.

It is not a de Polignac number, because 21344121 - 2¹ = 21344119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21344094 and 21344103.

It is not an unprimeable number, because it can be changed into a prime (21344131) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 395235 + ... + 395288.

It is an arithmetic number, because the mean of its divisors is an integer number (3952620).

Almost surely, 2^21344121 is an apocalyptic number.

It is an amenable number.

21344121 is a deficient number, since it is larger than the sum of its proper divisors (10276839).

21344121 is an equidigital number, since it uses as much as digits as its factorization.

21344121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 790532 (or 790526 counting only the distinct ones).

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

The square root of 21344121 is about 4619.9698050961. The cubic root of 21344121 is about 277.3912503021.

Adding to 21344121 its reverse (12144312), we get a palindrome (33488433).

The spelling of 21344121 in words is "twenty-one million, three hundred forty-four thousand, one hundred twenty-one".