51561319 has 2 divisors, whose sum is σ = 51561320. Its totient is φ = 51561318.

The previous prime is 51561317. The next prime is 51561329. The reversal of 51561319 is 91316515.

51561319 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 is a cyclic number.

It is not a de Polignac number, because 51561319 - 2¹ = 51561317 is a prime.

It is a super-2 number, since 2×51561319² = 5317139234039522, which contains 22 as substring.

Together with 51561317, 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 (51561311) 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, 25780659 + 25780660.

It is an arithmetic number, because the mean of its divisors is an integer number (25780660).

Almost surely, 2^51561319 is an apocalyptic number.

51561319 is a deficient number, since it is larger than the sum of its proper divisors (1).

51561319 is an equidigital number, since it uses as much as digits as its factorization.

51561319 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4050, while the sum is 31.

The square root of 51561319 is about 7180.6210734170. The cubic root of 51561319 is about 372.1985465532.

The spelling of 51561319 in words is "fifty-one million, five hundred sixty-one thousand, three hundred nineteen".