55986 has 32 divisors (see below), whose sum is σ = 135168. Its totient is φ = 15120.

The previous prime is 55967. The next prime is 55987. The reversal of 55986 is 68955.

55986 = T₂₈ + T₂₉ + ... + T₇₀.

It is a Curzon number.

It is a nialpdrome in base 6.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 55986.

It is not an unprimeable number, because it can be changed into a prime (55987) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1281 + ... + 1323.

It is an arithmetic number, because the mean of its divisors is an integer number (4224).

2⁵⁵⁹⁸⁶ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55986, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67584).

55986 is an abundant number, since it is smaller than the sum of its proper divisors (79182).

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

55986 is a wasteful number, since it uses less digits than its factorization.

55986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86.

The product of its digits is 10800, while the sum is 33.

The square root of 55986 is about 236.6136090761. The cubic root of 55986 is about 38.2554351711.

The spelling of 55986 in words is "fifty-five thousand, nine hundred eighty-six".