221842 has 4 divisors (see below), whose sum is σ = 332766. Its totient is φ = 110920.

The previous prime is 221831. The next prime is 221849. The reversal of 221842 is 248122.

221842 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Cunningham number, because it is equal to 471²+1.

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

It can be written as a sum of positive squares in only one way, i.e., 221841 + 1 = 471^2 + 1^2 .

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (221849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55459 + ... + 55462.

2²²¹⁸⁴² is an apocalyptic number.

221842 is a deficient number, since it is larger than the sum of its proper divisors (110924).

221842 is a wasteful number, since it uses less digits than its factorization.

221842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110923.

The product of its digits is 256, while the sum is 19.

The square root of 221842 is about 471.0010615699. The cubic root of 221842 is about 60.5361212251.

Adding to 221842 its reverse (248122), we get a palindrome (469964).

The spelling of 221842 in words is "two hundred twenty-one thousand, eight hundred forty-two".