51366 has 16 divisors (see below), whose sum is σ = 117504. Its totient is φ = 14664.

The previous prime is 51361. The next prime is 51383. The reversal of 51366 is 66315.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51361) by changing a digit.

51366 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 570 + ... + 653.

It is an arithmetic number, because the mean of its divisors is an integer number (7344).

2⁵¹³⁶⁶ is an apocalyptic number.

51366 is an abundant number, since it is smaller than the sum of its proper divisors (66138).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (58752).

51366 is a wasteful number, since it uses less digits than its factorization.

51366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1235.

The product of its digits is 540, while the sum is 21.

The square root of 51366 is about 226.6406847854. The cubic root of 51366 is about 37.1727977802.

The spelling of 51366 in words is "fifty-one thousand, three hundred sixty-six".