242731021 has 8 divisors (see below), whose sum is σ = 262231704. Its totient is φ = 223348800.

The previous prime is 242731009. The next prime is 242731031. The reversal of 242731021 is 120137242.

It can be written as a sum of positive squares in 4 ways, for example, as 29278921 + 213452100 = 5411^2 + 14610^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 242731021 - 2¹⁷ = 242599949 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 242730983 and 242731001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (242731031) 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, 25330 + ... + 33571.

It is an arithmetic number, because the mean of its divisors is an integer number (32778963).

Almost surely, 2^242731021 is an apocalyptic number.

It is an amenable number.

242731021 is a deficient number, since it is larger than the sum of its proper divisors (19500683).

242731021 is a wasteful number, since it uses less digits than its factorization.

242731021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59231.

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 242731021 is about 15579.8273738832. The cubic root of 242731021 is about 623.7948154621.

Adding to 242731021 its reverse (120137242), we get a palindrome (362868263).

The spelling of 242731021 in words is "two hundred forty-two million, seven hundred thirty-one thousand, twenty-one".