118211209 has 4 divisors (see below), whose sum is σ = 118234116. Its totient is φ = 118188304.

The previous prime is 118211207. The next prime is 118211227. The reversal of 118211209 is 902112811.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 902112811 = 89 ⋅10136099.

It can be written as a sum of positive squares in 2 ways, for example, as 55056400 + 63154809 = 7420^2 + 7947^2 .

It is a cyclic number.

It is not a de Polignac number, because 118211209 - 2¹ = 118211207 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (118211201) 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, 327 + ... + 15379.

It is an arithmetic number, because the mean of its divisors is an integer number (29558529).

Almost surely, 2^118211209 is an apocalyptic number.

It is an amenable number.

118211209 is a deficient number, since it is larger than the sum of its proper divisors (22907).

118211209 is an equidigital number, since it uses as much as digits as its factorization.

118211209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22906.

The product of its (nonzero) digits is 288, while the sum is 25.

The square root of 118211209 is about 10872.4978270865. The cubic root of 118211209 is about 490.7792806160.

The spelling of 118211209 in words is "one hundred eighteen million, two hundred eleven thousand, two hundred nine".