213442 has 4 divisors (see below), whose sum is σ = 320166. Its totient is φ = 106720.

The previous prime is 213407. The next prime is 213449. The reversal of 213442 is 244312.

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., 168921 + 44521 = 411^2 + 211^2 .

It is not an unprimeable number, because it can be changed into a prime (213449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53359 + ... + 53362.

2²¹³⁴⁴² is an apocalyptic number.

213442 is a deficient number, since it is larger than the sum of its proper divisors (106724).

213442 is a wasteful number, since it uses less digits than its factorization.

213442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106723.

The product of its digits is 192, while the sum is 16.

The square root of 213442 is about 461.9978354928. The cubic root of 213442 is about 59.7622069677.

Adding to 213442 its reverse (244312), we get a palindrome (457754).

The spelling of 213442 in words is "two hundred thirteen thousand, four hundred forty-two".