243328381 has 4 divisors (see below), whose sum is σ = 243412000. Its totient is φ = 243244764.

The previous prime is 243328373. The next prime is 243328387. The reversal of 243328381 is 183823342.

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 243328381 - 2³ = 243328373 is a prime.

It is a super-2 number, since 2×243328381² = 118417402000162322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243328387) 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, 37281 + ... + 43318.

It is an arithmetic number, because the mean of its divisors is an integer number (60853000).

It is a 2910-hyperperfect number.

Almost surely, 2^243328381 is an apocalyptic number.

It is an amenable number.

243328381 is a deficient number, since it is larger than the sum of its proper divisors (83619).

243328381 is an equidigital number, since it uses as much as digits as its factorization.

243328381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83618.

The product of its digits is 27648, while the sum is 34.

The square root of 243328381 is about 15598.9865375928. The cubic root of 243328381 is about 624.3061150430.

The spelling of 243328381 in words is "two hundred forty-three million, three hundred twenty-eight thousand, three hundred eighty-one".