65144450221 has 2 divisors, whose sum is σ = 65144450222. Its totient is φ = 65144450220.

The previous prime is 65144450201. The next prime is 65144450243. The reversal of 65144450221 is 12205444156.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64891958121 + 252492100 = 254739^2 + 15890^2 .

It is a cyclic number.

It is not a de Polignac number, because 65144450221 - 2⁹ = 65144449709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65144450201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32572225110 + 32572225111.

It is an arithmetic number, because the mean of its divisors is an integer number (32572225111).

Almost surely, 2^65144450221 is an apocalyptic number.

It is an amenable number.

65144450221 is a deficient number, since it is larger than the sum of its proper divisors (1).

65144450221 is an equidigital number, since it uses as much as digits as its factorization.

65144450221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38400, while the sum is 34.

Adding to 65144450221 its reverse (12205444156), we get a palindrome (77349894377).

The spelling of 65144450221 in words is "sixty-five billion, one hundred forty-four million, four hundred fifty thousand, two hundred twenty-one".