21320326343 has 4 divisors (see below), whose sum is σ = 22055510040. Its totient is φ = 20585142648.

The previous prime is 21320326337. The next prime is 21320326439. The reversal of 21320326343 is 34362302312.

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 21320326343 - 2⁸ = 21320326087 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 735183667 = 21320326343 / (2 + 1 + 3 + 2 + 0 + 3 + 2 + 6 + 3 + 4 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21320326243) 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, 367591805 + ... + 367591862.

It is an arithmetic number, because the mean of its divisors is an integer number (5513877510).

Almost surely, 2^21320326343 is an apocalyptic number.

21320326343 is a deficient number, since it is larger than the sum of its proper divisors (735183697).

21320326343 is an equidigital number, since it uses as much as digits as its factorization.

21320326343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 735183696.

The product of its (nonzero) digits is 15552, while the sum is 29.

Adding to 21320326343 its reverse (34362302312), we get a palindrome (55682628655).

The spelling of 21320326343 in words is "twenty-one billion, three hundred twenty million, three hundred twenty-six thousand, three hundred forty-three".