242021 has 4 divisors (see below), whose sum is σ = 260652. Its totient is φ = 223392.

The previous prime is 242009. The next prime is 242057. The reversal of 242021 is 120242.

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

It can be written as a sum of positive squares in 2 ways, for example, as 148996 + 93025 = 386^2 + 305^2 .

It is not a de Polignac number, because 242021 - 2¹⁰ = 240997 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 13.

It is a junction number, because it is equal to n+sod(n) for n = 241993 and 242011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (242521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9296 + ... + 9321.

It is an arithmetic number, because the mean of its divisors is an integer number (65163).

2²⁴²⁰²¹ is an apocalyptic number.

It is an amenable number.

242021 is a deficient number, since it is larger than the sum of its proper divisors (18631).

242021 is a wasteful number, since it uses less digits than its factorization.

242021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18630.

The product of its (nonzero) digits is 32, while the sum is 11.

The square root of 242021 is about 491.9562988722. The cubic root of 242021 is about 62.3185993435.

Adding to 242021 its reverse (120242), we get a palindrome (362263).

The spelling of 242021 in words is "two hundred forty-two thousand, twenty-one", and thus it is an iban number.