21331224031421 has 8 divisors (see below), whose sum is σ = 21338303521920. Its totient is φ = 21324145591008.

The previous prime is 21331224031393. The next prime is 21331224031433. The reversal of 21331224031421 is 12413042213312.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21331224031421 - 2¹⁴ = 21331224015037 is a prime.

It is a super-2 number, since 2×21331224031421² (a number of 27 digits) contains 22 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 (21331224031721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41465660 + ... + 41976938.

It is an arithmetic number, because the mean of its divisors is an integer number (2667287940240).

Almost surely, 2^{21331224031421} is an apocalyptic number.

It is an amenable number.

21331224031421 is a deficient number, since it is larger than the sum of its proper divisors (7079490499).

21331224031421 is an equidigital number, since it uses as much as digits as its factorization.

21331224031421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 525043.

The product of its (nonzero) digits is 6912, while the sum is 29.

Adding to 21331224031421 its reverse (12413042213312), we get a palindrome (33744266244733).

The spelling of 21331224031421 in words is "twenty-one trillion, three hundred thirty-one billion, two hundred twenty-four million, thirty-one thousand, four hundred twenty-one".