21341621 has 8 divisors (see below), whose sum is σ = 24454464. Its totient is φ = 18244800.

The previous prime is 21341611. The next prime is 21341627. The reversal of 21341621 is 12614312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21341621 - 2⁶ = 21341557 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21341593 and 21341602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21341627) 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 7 ways as a sum of consecutive naturals, for example, 995 + ... + 6608.

It is an arithmetic number, because the mean of its divisors is an integer number (3056808).

Almost surely, 2^21341621 is an apocalyptic number.

It is an amenable number.

21341621 is a deficient number, since it is larger than the sum of its proper divisors (3112843).

21341621 is an equidigital number, since it uses as much as digits as its factorization.

21341621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8011.

The product of its digits is 288, while the sum is 20.

The square root of 21341621 is about 4619.6992326341. The cubic root of 21341621 is about 277.3804197600.

Adding to 21341621 its reverse (12614312), we get a palindrome (33955933).

The spelling of 21341621 in words is "twenty-one million, three hundred forty-one thousand, six hundred twenty-one".