51808501 has 2 divisors, whose sum is σ = 51808502. Its totient is φ = 51808500.

The previous prime is 51808499. The next prime is 51808511. The reversal of 51808501 is 10580815.

51808501 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., 51466276 + 342225 = 7174^2 + 585^2 .

It is a cyclic number.

It is not a de Polignac number, because 51808501 - 2¹ = 51808499 is a prime.

Together with 51808499, 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 51808501.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51808511) 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, 25904250 + 25904251.

It is an arithmetic number, because the mean of its divisors is an integer number (25904251).

Almost surely, 2^51808501 is an apocalyptic number.

It is an amenable number.

51808501 is a deficient number, since it is larger than the sum of its proper divisors (1).

51808501 is an equidigital number, since it uses as much as digits as its factorization.

51808501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1600, while the sum is 28.

The square root of 51808501 is about 7197.8122370620. The cubic root of 51808501 is about 372.7923647986.

The spelling of 51808501 in words is "fifty-one million, eight hundred eight thousand, five hundred one".