21053821184189 has 4 divisors (see below), whose sum is σ = 21054807748860. Its totient is φ = 21052834619520.

The previous prime is 21053821184177. The next prime is 21053821184239. The reversal of 21053821184189 is 98148112835012.

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

It can be written as a sum of positive squares in 2 ways, for example, as 19567201851289 + 1486619332900 = 4423483^2 + 1219270^2 .

It is a cyclic number.

It is not a de Polignac number, because 21053821184189 - 2¹⁶ = 21053821118653 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21053821184189.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21653821184189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 493250324 + ... + 493293005.

It is an arithmetic number, because the mean of its divisors is an integer number (5263701937215).

Almost surely, 2^{21053821184189} is an apocalyptic number.

It is an amenable number.

21053821184189 is a deficient number, since it is larger than the sum of its proper divisors (986564671).

21053821184189 is an equidigital number, since it uses as much as digits as its factorization.

21053821184189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 986564670.

The product of its (nonzero) digits is 1105920, while the sum is 53.

The spelling of 21053821184189 in words is "twenty-one trillion, fifty-three billion, eight hundred twenty-one million, one hundred eighty-four thousand, one hundred eighty-nine".