63605855221 has 2 divisors, whose sum is σ = 63605855222. Its totient is φ = 63605855220.

The previous prime is 63605855197. The next prime is 63605855239. The reversal of 63605855221 is 12255850636.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43693540900 + 19912314321 = 209030^2 + 141111^2 .

It is a cyclic number.

It is not a de Polignac number, because 63605855221 - 2⁹ = 63605854709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (63605855021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31802927610 + 31802927611.

It is an arithmetic number, because the mean of its divisors is an integer number (31802927611).

Almost surely, 2^63605855221 is an apocalyptic number.

It is an amenable number.

63605855221 is a deficient number, since it is larger than the sum of its proper divisors (1).

63605855221 is an equidigital number, since it uses as much as digits as its factorization.

63605855221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432000, while the sum is 43.

The spelling of 63605855221 in words is "sixty-three billion, six hundred five million, eight hundred fifty-five thousand, two hundred twenty-one".