21321344343243 has 32 divisors (see below), whose sum is σ = 32622866035200. Its totient is φ = 12133687104000.

The previous prime is 21321344343239. The next prime is 21321344343251. The reversal of 21321344343243 is 34234344312312.

It is not a de Polignac number, because 21321344343243 - 2² = 21321344343239 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21321344343293) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 46414521 + ... + 46871637.

It is an arithmetic number, because the mean of its divisors is an integer number (1019464563600).

Almost surely, 2^{21321344343243} is an apocalyptic number.

21321344343243 is a deficient number, since it is larger than the sum of its proper divisors (11301521691957).

21321344343243 is a wasteful number, since it uses less digits than its factorization.

21321344343243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 466227.

The product of its digits is 497664, while the sum is 39.

Adding to 21321344343243 its reverse (34234344312312), we get a palindrome (55555688655555).

The spelling of 21321344343243 in words is "twenty-one trillion, three hundred twenty-one billion, three hundred forty-four million, three hundred forty-three thousand, two hundred forty-three".