51666786 has 24 divisors (see below), whose sum is σ = 116812800. Its totient is φ = 16473336.

The previous prime is 51666773. The next prime is 51666787. The reversal of 51666786 is 68766615.

51666786 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (51666787) 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 11 ways as a sum of consecutive naturals, for example, 61986 + ... + 62813.

It is an arithmetic number, because the mean of its divisors is an integer number (4867200).

Almost surely, 2^51666786 is an apocalyptic number.

51666786 is an abundant number, since it is smaller than the sum of its proper divisors (65146014).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51666786 is a wasteful number, since it uses less digits than its factorization.

51666786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124830 (or 124827 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 51666786 is about 7187.9611852040. The cubic root of 51666786 is about 372.4521470592.

The spelling of 51666786 in words is "fifty-one million, six hundred sixty-six thousand, seven hundred eighty-six".