51866918 has 4 divisors (see below), whose sum is σ = 77800380. Its totient is φ = 25933458.

The previous prime is 51866869. The next prime is 51866921. The reversal of 51866918 is 81966815.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12966728 + ... + 12966731.

It is an arithmetic number, because the mean of its divisors is an integer number (19450095).

Almost surely, 2^51866918 is an apocalyptic number.

51866918 is a deficient number, since it is larger than the sum of its proper divisors (25933462).

51866918 is a wasteful number, since it uses less digits than its factorization.

51866918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25933461.

The product of its digits is 103680, while the sum is 44.

The square root of 51866918 is about 7201.8690629586. The cubic root of 51866918 is about 372.9324269583.

The spelling of 51866918 in words is "fifty-one million, eight hundred sixty-six thousand, nine hundred eighteen".