51550352221 has 2 divisors, whose sum is σ = 51550352222. Its totient is φ = 51550352220.

The previous prime is 51550352173. The next prime is 51550352233. The reversal of 51550352221 is 12225305515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51443229721 + 107122500 = 226811^2 + 10350^2 .

It is a cyclic number.

It is not a de Polignac number, because 51550352221 - 2⁹ = 51550351709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51550352621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25775176110 + 25775176111.

It is an arithmetic number, because the mean of its divisors is an integer number (25775176111).

Almost surely, 2^51550352221 is an apocalyptic number.

It is an amenable number.

51550352221 is a deficient number, since it is larger than the sum of its proper divisors (1).

51550352221 is an equidigital number, since it uses as much as digits as its factorization.

51550352221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15000, while the sum is 31.

Adding to 51550352221 its reverse (12225305515), we get a palindrome (63775657736).

The spelling of 51550352221 in words is "fifty-one billion, five hundred fifty million, three hundred fifty-two thousand, two hundred twenty-one".