221913 has 8 divisors (see below), whose sum is σ = 328800. Its totient is φ = 147924.

The previous prime is 221909. The next prime is 221941. The reversal of 221913 is 319122.

It is a happy number.

It is not a de Polignac number, because 221913 - 2² = 221909 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221953) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4083 + ... + 4136.

It is an arithmetic number, because the mean of its divisors is an integer number (41100).

2²²¹⁹¹³ is an apocalyptic number.

It is an amenable number.

221913 is a deficient number, since it is larger than the sum of its proper divisors (106887).

221913 is an equidigital number, since it uses as much as digits as its factorization.

221913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8228 (or 8222 counting only the distinct ones).

The product of its digits is 108, while the sum is 18.

The square root of 221913 is about 471.0764269203. The cubic root of 221913 is about 60.5425786830.

The spelling of 221913 in words is "two hundred twenty-one thousand, nine hundred thirteen".