21243301405 has 16 divisors (see below), whose sum is σ = 28412095680. Its totient is φ = 15153115392.

The previous prime is 21243301403. The next prime is 21243301421. The reversal of 21243301405 is 50410334212.

It is a cyclic number.

It is not a de Polignac number, because 21243301405 - 2¹ = 21243301403 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21243301405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21243301403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6575259 + ... + 6578488.

It is an arithmetic number, because the mean of its divisors is an integer number (1775755980).

Almost surely, 2^21243301405 is an apocalyptic number.

It is an amenable number.

21243301405 is a deficient number, since it is larger than the sum of its proper divisors (7168794275).

21243301405 is a wasteful number, since it uses less digits than its factorization.

21243301405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13153788.

The product of its (nonzero) digits is 2880, while the sum is 25.

Adding to 21243301405 its reverse (50410334212), we get a palindrome (71653635617).

The spelling of 21243301405 in words is "twenty-one billion, two hundred forty-three million, three hundred one thousand, four hundred five".