242243021 has 4 divisors (see below), whose sum is σ = 250057344. Its totient is φ = 234428700.

The previous prime is 242243011. The next prime is 242243051. The reversal of 242243021 is 120342242.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 120342242 = 2 ⋅60171121.

It is a cyclic number.

It is not a de Polignac number, because 242243021 - 2¹⁸ = 241980877 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 242242984 and 242243002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (242243011) 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, 3907115 + ... + 3907176.

It is an arithmetic number, because the mean of its divisors is an integer number (62514336).

Almost surely, 2^242243021 is an apocalyptic number.

It is an amenable number.

242243021 is a deficient number, since it is larger than the sum of its proper divisors (7814323).

242243021 is an equidigital number, since it uses as much as digits as its factorization.

242243021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7814322.

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 242243021 is about 15564.1582168776. The cubic root of 242243021 is about 623.3764976893.

Adding to 242243021 its reverse (120342242), we get a palindrome (362585263).

The spelling of 242243021 in words is "two hundred forty-two million, two hundred forty-three thousand, twenty-one".