243820111 has 4 divisors (see below), whose sum is σ = 247817224. Its totient is φ = 239823000.

The previous prime is 243820097. The next prime is 243820117. The reversal of 243820111 is 111028342.

It is a happy number.

243820111 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.

It is a cyclic number.

It is not a de Polignac number, because 243820111 - 2¹⁵ = 243787343 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243820117) 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, 1998465 + ... + 1998586.

It is an arithmetic number, because the mean of its divisors is an integer number (61954306).

Almost surely, 2^243820111 is an apocalyptic number.

243820111 is a deficient number, since it is larger than the sum of its proper divisors (3997113).

243820111 is an equidigital number, since it uses as much as digits as its factorization.

243820111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3997112.

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 243820111 is about 15614.7401835573. The cubic root of 243820111 is about 624.7263749444.

Adding to 243820111 its reverse (111028342), we get a palindrome (354848453).

The spelling of 243820111 in words is "two hundred forty-three million, eight hundred twenty thousand, one hundred eleven".