21667142321243 has 4 divisors (see below), whose sum is σ = 22609191987408. Its totient is φ = 20725092655080.

The previous prime is 21667142321221. The next prime is 21667142321263. The reversal of 21667142321243 is 34212324176612.

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 21667142321243 - 2⁸ = 21667142320987 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21667142321194 and 21667142321203.

It is not an unprimeable number, because it can be changed into a prime (21667142321263) 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, 471024833048 + ... + 471024833093.

It is an arithmetic number, because the mean of its divisors is an integer number (5652297996852).

Almost surely, 2^{21667142321243} is an apocalyptic number.

21667142321243 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21667142321243 is a deficient number, since it is larger than the sum of its proper divisors (942049666165).

21667142321243 is an equidigital number, since it uses as much as digits as its factorization.

21667142321243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 942049666164.

The product of its digits is 580608, while the sum is 44.

Adding to 21667142321243 its reverse (34212324176612), we get a palindrome (55879466497855).

The spelling of 21667142321243 in words is "twenty-one trillion, six hundred sixty-seven billion, one hundred forty-two million, three hundred twenty-one thousand, two hundred forty-three".