51321289 has 2 divisors, whose sum is σ = 51321290. Its totient is φ = 51321288.

The previous prime is 51321287. The next prime is 51321293. The reversal of 51321289 is 98212315.

51321289 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34715664 + 16605625 = 5892^2 + 4075^2 .

It is a cyclic number.

It is not a de Polignac number, because 51321289 - 2¹ = 51321287 is a prime.

Together with 51321287, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 51321289.

It is not a weakly prime, because it can be changed into another prime (51321287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25660644 + 25660645.

It is an arithmetic number, because the mean of its divisors is an integer number (25660645).

Almost surely, 2^51321289 is an apocalyptic number.

It is an amenable number.

51321289 is a deficient number, since it is larger than the sum of its proper divisors (1).

51321289 is an equidigital number, since it uses as much as digits as its factorization.

51321289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4320, while the sum is 31.

The square root of 51321289 is about 7163.8878411097. The cubic root of 51321289 is about 371.6200909101.

The spelling of 51321289 in words is "fifty-one million, three hundred twenty-one thousand, two hundred eighty-nine".