21252134534321 has 2 divisors, whose sum is σ = 21252134534322. Its totient is φ = 21252134534320.

The previous prime is 21252134534261. The next prime is 21252134534347. The reversal of 21252134534321 is 12343543125212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20986431399025 + 265703135296 = 4581095^2 + 515464^2 .

It is a cyclic number.

It is not a de Polignac number, because 21252134534321 - 2¹⁸ = 21252134272177 is a prime.

It is not a weakly prime, because it can be changed into another prime (21252134534821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10626067267160 + 10626067267161.

It is an arithmetic number, because the mean of its divisors is an integer number (10626067267161).

Almost surely, 2^{21252134534321} is an apocalyptic number.

It is an amenable number.

21252134534321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21252134534321 is an equidigital number, since it uses as much as digits as its factorization.

21252134534321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 172800, while the sum is 38.

Adding to 21252134534321 its reverse (12343543125212), we get a palindrome (33595677659533).

The spelling of 21252134534321 in words is "twenty-one trillion, two hundred fifty-two billion, one hundred thirty-four million, five hundred thirty-four thousand, three hundred twenty-one".