21213312343 has 2 divisors, whose sum is σ = 21213312344. Its totient is φ = 21213312342.

The previous prime is 21213312319. The next prime is 21213312361. The reversal of 21213312343 is 34321331212.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21213312343 is a prime.

It is a super-2 number, since 2×21213312343² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21213319343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606656171 + 10606656172.

It is an arithmetic number, because the mean of its divisors is an integer number (10606656172).

Almost surely, 2^21213312343 is an apocalyptic number.

21213312343 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213312343 is an equidigital number, since it uses as much as digits as its factorization.

21213312343 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 25.

Adding to 21213312343 its reverse (34321331212), we get a palindrome (55534643555).

The spelling of 21213312343 in words is "twenty-one billion, two hundred thirteen million, three hundred twelve thousand, three hundred forty-three".