243924661 has 4 divisors (see below), whose sum is σ = 244825024. Its totient is φ = 243024300.

The previous prime is 243924631. The next prime is 243924677. The reversal of 243924661 is 166429342.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 243924661 - 2⁷ = 243924533 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 243924661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243924601) 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, 449775 + ... + 450316.

It is an arithmetic number, because the mean of its divisors is an integer number (61206256).

Almost surely, 2^243924661 is an apocalyptic number.

It is an amenable number.

243924661 is a deficient number, since it is larger than the sum of its proper divisors (900363).

243924661 is an equidigital number, since it uses as much as digits as its factorization.

243924661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 900362.

The product of its digits is 62208, while the sum is 37.

The square root of 243924661 is about 15618.0876230094. The cubic root of 243924661 is about 624.8156563532.

The spelling of 243924661 in words is "two hundred forty-three million, nine hundred twenty-four thousand, six hundred sixty-one".