51616391 has 2 divisors, whose sum is σ = 51616392. Its totient is φ = 51616390.

The previous prime is 51616381. The next prime is 51616447. The reversal of 51616391 is 19361615.

It is a happy number.

51616391 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 51616391 - 2¹⁴ = 51600007 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51616321) 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, 25808195 + 25808196.

It is an arithmetic number, because the mean of its divisors is an integer number (25808196).

Almost surely, 2^51616391 is an apocalyptic number.

51616391 is a deficient number, since it is larger than the sum of its proper divisors (1).

51616391 is an equidigital number, since it uses as much as digits as its factorization.

51616391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4860, while the sum is 32.

The square root of 51616391 is about 7184.4548157811. The cubic root of 51616391 is about 372.3310129401.

The spelling of 51616391 in words is "fifty-one million, six hundred sixteen thousand, three hundred ninety-one".