51561907 has 2 divisors, whose sum is σ = 51561908. Its totient is φ = 51561906.

The previous prime is 51561899. The next prime is 51561919. The reversal of 51561907 is 70916515.

51561907 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 51561907 - 2³ = 51561899 is a prime.

It is not a weakly prime, because it can be changed into another prime (51561997) 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, 25780953 + 25780954.

It is an arithmetic number, because the mean of its divisors is an integer number (25780954).

Almost surely, 2^51561907 is an apocalyptic number.

51561907 is a deficient number, since it is larger than the sum of its proper divisors (1).

51561907 is an equidigital number, since it uses as much as digits as its factorization.

51561907 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9450, while the sum is 34.

The square root of 51561907 is about 7180.6620168338. The cubic root of 51561907 is about 372.1999613858.

The spelling of 51561907 in words is "fifty-one million, five hundred sixty-one thousand, nine hundred seven".