221903 has 4 divisors (see below), whose sum is σ = 242088. Its totient is φ = 201720.

The previous prime is 221891. The next prime is 221909. The reversal of 221903 is 309122.

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 221903 - 2¹⁰ = 220879 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221909) 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, 10076 + ... + 10097.

It is an arithmetic number, because the mean of its divisors is an integer number (60522).

2²²¹⁹⁰³ is an apocalyptic number.

221903 is a deficient number, since it is larger than the sum of its proper divisors (20185).

221903 is a wasteful number, since it uses less digits than its factorization.

221903 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20184.

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 221903 is about 471.0658128118. The cubic root of 221903 is about 60.5416692652.

The spelling of 221903 in words is "two hundred twenty-one thousand, nine hundred three".