21242021323231 has 2 divisors, whose sum is σ = 21242021323232. Its totient is φ = 21242021323230.

The previous prime is 21242021323219. The next prime is 21242021323273. The reversal of 21242021323231 is 13232312024212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21242021323231 - 2¹⁵ = 21242021290463 is a prime.

It is a super-2 number, since 2×21242021323231² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21242021323231.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21242021323291) 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 as a sum of consecutive naturals, namely, 10621010661615 + 10621010661616.

It is an arithmetic number, because the mean of its divisors is an integer number (10621010661616).

Almost surely, 2^{21242021323231} is an apocalyptic number.

21242021323231 is a deficient number, since it is larger than the sum of its proper divisors (1).

21242021323231 is an equidigital number, since it uses as much as digits as its factorization.

21242021323231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 28.

Adding to 21242021323231 its reverse (13232312024212), we get a palindrome (34474333347443).

The spelling of 21242021323231 in words is "twenty-one trillion, two hundred forty-two billion, twenty-one million, three hundred twenty-three thousand, two hundred thirty-one".