118243509 has 4 divisors (see below), whose sum is σ = 157658016. Its totient is φ = 78829004.

The previous prime is 118243459. The next prime is 118243511. The reversal of 118243509 is 905342811.

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 118243509 - 2¹³ = 118235317 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 118243509.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (118243589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19707249 + ... + 19707254.

It is an arithmetic number, because the mean of its divisors is an integer number (39414504).

Almost surely, 2^118243509 is an apocalyptic number.

It is an amenable number.

118243509 is a deficient number, since it is larger than the sum of its proper divisors (39414507).

118243509 is an equidigital number, since it uses as much as digits as its factorization.

118243509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39414506.

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 118243509 is about 10873.9831248720. The cubic root of 118243509 is about 490.8239766796.

The spelling of 118243509 in words is "one hundred eighteen million, two hundred forty-three thousand, five hundred nine".