118115209 has 2 divisors, whose sum is σ = 118115210. Its totient is φ = 118115208.

The previous prime is 118115203. The next prime is 118115213. The reversal of 118115209 is 902511811.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 88303609 + 29811600 = 9397^2 + 5460^2 .

It is a cyclic number.

It is not a de Polignac number, because 118115209 - 2²³ = 109726601 is a prime.

It is a super-2 number, since 2×118115209² = 27902405194227362, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (118115203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 59057604 + 59057605.

It is an arithmetic number, because the mean of its divisors is an integer number (59057605).

Almost surely, 2^118115209 is an apocalyptic number.

It is an amenable number.

118115209 is a deficient number, since it is larger than the sum of its proper divisors (1).

118115209 is an equidigital number, since it uses as much as digits as its factorization.

118115209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 28.

The square root of 118115209 is about 10868.0821215153. The cubic root of 118115209 is about 490.6463897473.

It can be divided in two parts, 11811 and 5209, that added together give a triangular number (17020 = T₁₈₄).

The spelling of 118115209 in words is "one hundred eighteen million, one hundred fifteen thousand, two hundred nine".