21123311433343 has 4 divisors (see below), whose sum is σ = 24140927352400. Its totient is φ = 18105695514288.

The previous prime is 21123311433317. The next prime is 21123311433349. The reversal of 21123311433343 is 34333411332112.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21123311433343 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21123311433299 and 21123311433308.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123311433349) 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, 1508807959518 + ... + 1508807959531.

It is an arithmetic number, because the mean of its divisors is an integer number (6035231838100).

Almost surely, 2^{21123311433343} is an apocalyptic number.

21123311433343 is a deficient number, since it is larger than the sum of its proper divisors (3017615919057).

21123311433343 is an equidigital number, since it uses as much as digits as its factorization.

21123311433343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3017615919056.

The product of its digits is 46656, while the sum is 34.

Adding to 21123311433343 its reverse (34333411332112), we get a palindrome (55456722765455).

The spelling of 21123311433343 in words is "twenty-one trillion, one hundred twenty-three billion, three hundred eleven million, four hundred thirty-three thousand, three hundred forty-three".