55891 has 4 divisors (see below), whose sum is σ = 60984. Its totient is φ = 50800.

The previous prime is 55889. The next prime is 55897. The reversal of 55891 is 19855.

55891 = T₆₀ + T₆₁ + ... + T₈₁.

55891 = 94² + 95² + ... + 99².

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

It is a cyclic number.

It is not a de Polignac number, because 55891 - 2¹ = 55889 is a prime.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (55897) 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, 2530 + ... + 2551.

It is an arithmetic number, because the mean of its divisors is an integer number (15246).

2⁵⁵⁸⁹¹ is an apocalyptic number.

55891 is a deficient number, since it is larger than the sum of its proper divisors (5093).

55891 is a wasteful number, since it uses less digits than its factorization.

55891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5092.

The product of its digits is 1800, while the sum is 28.

The square root of 55891 is about 236.4127746125. The cubic root of 55891 is about 38.2337849735.

It can be divided in two parts, 55 and 891, that added together give a triangular number (946 = T₄₃).

The spelling of 55891 in words is "fifty-five thousand, eight hundred ninety-one".