21443503101421 has 4 divisors (see below), whose sum is σ = 21443827660992. Its totient is φ = 21443178541852.

The previous prime is 21443503101403. The next prime is 21443503101457. The reversal of 21443503101421 is 12410130534412.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21443503101421 - 2⁹ = 21443503100909 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 (21443503101481) 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, 162180661 + ... + 162312826.

It is an arithmetic number, because the mean of its divisors is an integer number (5360956915248).

Almost surely, 2^{21443503101421} is an apocalyptic number.

It is an amenable number.

21443503101421 is a deficient number, since it is larger than the sum of its proper divisors (324559571).

21443503101421 is an equidigital number, since it uses as much as digits as its factorization.

21443503101421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324559570.

The product of its (nonzero) digits is 11520, while the sum is 31.

Adding to 21443503101421 its reverse (12410130534412), we get a palindrome (33853633635833).

The spelling of 21443503101421 in words is "twenty-one trillion, four hundred forty-three billion, five hundred three million, one hundred one thousand, four hundred twenty-one".