51415049221 has 2 divisors, whose sum is σ = 51415049222. Its totient is φ = 51415049220.

The previous prime is 51415049219. The next prime is 51415049249. The reversal of 51415049221 is 12294051415.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44316144196 + 7098905025 = 210514^2 + 84255^2 .

It is a cyclic number.

It is not a de Polignac number, because 51415049221 - 2¹ = 51415049219 is a prime.

Together with 51415049219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51415049201) 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, 25707524610 + 25707524611.

It is an arithmetic number, because the mean of its divisors is an integer number (25707524611).

Almost surely, 2^51415049221 is an apocalyptic number.

It is an amenable number.

51415049221 is a deficient number, since it is larger than the sum of its proper divisors (1).

51415049221 is an equidigital number, since it uses as much as digits as its factorization.

51415049221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14400, while the sum is 34.

The spelling of 51415049221 in words is "fifty-one billion, four hundred fifteen million, forty-nine thousand, two hundred twenty-one".