21663365134223 has 4 divisors (see below), whose sum is σ = 22248861489240. Its totient is φ = 21077868779208.

The previous prime is 21663365134139. The next prime is 21663365134231. The reversal of 21663365134223 is 32243156336612.

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 21663365134223 - 2⁸ = 21663365133967 is a prime.

It is a super-4 number, since 4×21663365134223⁴ (a number of 54 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21663365139223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 292748177453 + ... + 292748177526.

It is an arithmetic number, because the mean of its divisors is an integer number (5562215372310).

Almost surely, 2^{21663365134223} is an apocalyptic number.

21663365134223 is a deficient number, since it is larger than the sum of its proper divisors (585496355017).

21663365134223 is an equidigital number, since it uses as much as digits as its factorization.

21663365134223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 585496355016.

The product of its digits is 2799360, while the sum is 47.

The spelling of 21663365134223 in words is "twenty-one trillion, six hundred sixty-three billion, three hundred sixty-five million, one hundred thirty-four thousand, two hundred twenty-three".