21252203150221 has 2 divisors, whose sum is σ = 21252203150222. Its totient is φ = 21252203150220.

The previous prime is 21252203150179. The next prime is 21252203150257. The reversal of 21252203150221 is 12205130225212.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18940434947721 + 2311768202500 = 4352061^2 + 1520450^2 .

It is a cyclic number.

It is not a de Polignac number, because 21252203150221 - 2⁷ = 21252203150093 is a prime.

It is a super-2 number, since 2×21252203150221² (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 21252203150221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21252203150291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10626101575110 + 10626101575111.

It is an arithmetic number, because the mean of its divisors is an integer number (10626101575111).

Almost surely, 2^{21252203150221} is an apocalyptic number.

It is an amenable number.

21252203150221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21252203150221 is an equidigital number, since it uses as much as digits as its factorization.

21252203150221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4800, while the sum is 28.

Adding to 21252203150221 its reverse (12205130225212), we get a palindrome (33457333375433).

The spelling of 21252203150221 in words is "twenty-one trillion, two hundred fifty-two billion, two hundred three million, one hundred fifty thousand, two hundred twenty-one".