21814665641533 has 4 divisors (see below), whose sum is σ = 21814677232348. Its totient is φ = 21814654050720.

The previous prime is 21814665641497. The next prime is 21814665641543. The reversal of 21814665641533 is 33514656641812.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 5908312212804 + 15906353428729 = 2430702^2 + 3988277^2 .

It is a cyclic number.

It is not a de Polignac number, because 21814665641533 - 2¹⁷ = 21814665510461 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21814665641543) 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, 2248866 + ... + 6977587.

It is an arithmetic number, because the mean of its divisors is an integer number (5453669308087).

Almost surely, 2^{21814665641533} is an apocalyptic number.

It is an amenable number.

21814665641533 is a deficient number, since it is larger than the sum of its proper divisors (11590815).

21814665641533 is an equidigital number, since it uses as much as digits as its factorization.

21814665641533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11590814.

The product of its digits is 12441600, while the sum is 55.

The spelling of 21814665641533 in words is "twenty-one trillion, eight hundred fourteen billion, six hundred sixty-five million, six hundred forty-one thousand, five hundred thirty-three".