53999 has 4 divisors (see below), whose sum is σ = 58920. Its totient is φ = 49080.

The previous prime is 53993. The next prime is 54001. The reversal of 53999 is 99935.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-53999 is a prime.

It is a Duffinian number.

53999 is a modest number, since divided by 999 gives 53 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2444 + ... + 2465.

It is an arithmetic number, because the mean of its divisors is an integer number (14730).

2⁵³⁹⁹⁹ is an apocalyptic number.

53999 is a deficient number, since it is larger than the sum of its proper divisors (4921).

53999 is a wasteful number, since it uses less digits than its factorization.

53999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4920.

The product of its digits is 10935, while the sum is 35.

The square root of 53999 is about 232.3768491051. The cubic root of 53999 is about 37.7973981767.

It can be divided in two parts, 539 and 99, that multiplied together give a square (53361 = 231²).

The spelling of 53999 in words is "fifty-three thousand, nine hundred ninety-nine".