242649921 has 4 divisors (see below), whose sum is σ = 323533232. Its totient is φ = 161766612.

The previous prime is 242649917. The next prime is 242649929. The reversal of 242649921 is 129946242.

242649921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is not a de Polignac number, because 242649921 - 2² = 242649917 is a prime.

It is a super-2 number, since 2×242649921² = 117757968322612482, which contains 22 as substring.

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 242649921.

It is not an unprimeable number, because it can be changed into a prime (242649929) 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, 40441651 + ... + 40441656.

It is an arithmetic number, because the mean of its divisors is an integer number (80883308).

Almost surely, 2^242649921 is an apocalyptic number.

It is an amenable number.

242649921 is a deficient number, since it is larger than the sum of its proper divisors (80883311).

242649921 is an equidigital number, since it uses as much as digits as its factorization.

242649921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80883310.

The product of its digits is 62208, while the sum is 39.

The square root of 242649921 is about 15577.2244318428. The cubic root of 242649921 is about 623.7253347194.

The spelling of 242649921 in words is "two hundred forty-two million, six hundred forty-nine thousand, nine hundred twenty-one".