51866851 has 4 divisors (see below), whose sum is σ = 51881392. Its totient is φ = 51852312.

The previous prime is 51866831. The next prime is 51866869. The reversal of 51866851 is 15866815.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 15866815 = 5 ⋅3173363.

It is a cyclic number.

It is not a de Polignac number, because 51866851 - 2¹¹ = 51864803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51866831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2146 + ... + 10408.

It is an arithmetic number, because the mean of its divisors is an integer number (12970348).

Almost surely, 2^51866851 is an apocalyptic number.

51866851 is a deficient number, since it is larger than the sum of its proper divisors (14541).

51866851 is an equidigital number, since it uses as much as digits as its factorization.

51866851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14540.

The product of its digits is 57600, while the sum is 40.

The square root of 51866851 is about 7201.8644113868. The cubic root of 51866851 is about 372.9322663775.

The spelling of 51866851 in words is "fifty-one million, eight hundred sixty-six thousand, eight hundred fifty-one".