51868865 has 4 divisors (see below), whose sum is σ = 62242644. Its totient is φ = 41495088.

The previous prime is 51868807. The next prime is 51868867. The reversal of 51868865 is 56886815.

51868865 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56886815 = 5 ⋅11377363.

It can be written as a sum of positive squares in 2 ways, for example, as 17247409 + 34621456 = 4153^2 + 5884^2 .

It is a cyclic number.

It is not a de Polignac number, because 51868865 - 2⁶ = 51868801 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51868867) 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 in 3 ways as a sum of consecutive naturals, for example, 5186882 + ... + 5186891.

It is an arithmetic number, because the mean of its divisors is an integer number (15560661).

Almost surely, 2^51868865 is an apocalyptic number.

It is an amenable number.

51868865 is a deficient number, since it is larger than the sum of its proper divisors (10373779).

51868865 is a wasteful number, since it uses less digits than its factorization.

51868865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10373778.

The product of its digits is 460800, while the sum is 47.

The square root of 51868865 is about 7202.0042349335. The cubic root of 51868865 is about 372.9370933261.

The spelling of 51868865 in words is "fifty-one million, eight hundred sixty-eight thousand, eight hundred sixty-five".