21144321343 has 4 divisors (see below), whose sum is σ = 21147752808. Its totient is φ = 21140889880.

The previous prime is 21144321281. The next prime is 21144321347. The reversal of 21144321343 is 34312344112.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21144321343 - 2³³ = 12554386751 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21144321347) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1706473 + ... + 1718818.

It is an arithmetic number, because the mean of its divisors is an integer number (5286938202).

Almost surely, 2^21144321343 is an apocalyptic number.

21144321343 is a deficient number, since it is larger than the sum of its proper divisors (3431465).

21144321343 is an equidigital number, since it uses as much as digits as its factorization.

21144321343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3431464.

The product of its digits is 6912, while the sum is 28.

Adding to 21144321343 its reverse (34312344112), we get a palindrome (55456665455).

The spelling of 21144321343 in words is "twenty-one billion, one hundred forty-four million, three hundred twenty-one thousand, three hundred forty-three".