242173621 has 8 divisors (see below), whose sum is σ = 249627320. Its totient is φ = 234767808.

The previous prime is 242173609. The next prime is 242173651. The reversal of 242173621 is 126371242.

It can be written as a sum of positive squares in 4 ways, for example, as 2852721 + 239320900 = 1689^2 + 15470^2 .

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 242173621 - 2⁷ = 242173493 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 242173621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (242173651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1566 + ... + 22063.

It is an arithmetic number, because the mean of its divisors is an integer number (31203415).

Almost surely, 2^242173621 is an apocalyptic number.

It is an amenable number.

242173621 is a deficient number, since it is larger than the sum of its proper divisors (7453699).

242173621 is a wasteful number, since it uses less digits than its factorization.

242173621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23943.

The product of its digits is 4032, while the sum is 28.

The square root of 242173621 is about 15561.9285758546. The cubic root of 242173621 is about 623.3169618001.

The spelling of 242173621 in words is "two hundred forty-two million, one hundred seventy-three thousand, six hundred twenty-one".