212563365221 has 2 divisors, whose sum is σ = 212563365222. Its totient is φ = 212563365220.

The previous prime is 212563365169. The next prime is 212563365269. The reversal of 212563365221 is 122563365212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 205403836225 + 7159528996 = 453215^2 + 84614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212563365221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212563365121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106281682610 + 106281682611.

It is an arithmetic number, because the mean of its divisors is an integer number (106281682611).

Almost surely, 2^212563365221 is an apocalyptic number.

It is an amenable number.

212563365221 is a deficient number, since it is larger than the sum of its proper divisors (1).

212563365221 is an equidigital number, since it uses as much as digits as its factorization.

212563365221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 129600, while the sum is 38.

Subtracting from 212563365221 its reverse (122563365212), we obtain a palindrome (90000000009).

The spelling of 212563365221 in words is "two hundred twelve billion, five hundred sixty-three million, three hundred sixty-five thousand, two hundred twenty-one".