136242209 has 4 divisors (see below), whose sum is σ = 136265604. Its totient is φ = 136218816.

The previous prime is 136242191. The next prime is 136242229. The reversal of 136242209 is 902242631.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 902242631 = 31 ⋅29104601.

It can be written as a sum of positive squares in 2 ways, for example, as 122589184 + 13653025 = 11072^2 + 3695^2 .

It is a cyclic number.

It is not a de Polignac number, because 136242209 - 2¹⁶ = 136176673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (136242229) 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, 4709 + ... + 17165.

It is an arithmetic number, because the mean of its divisors is an integer number (34066401).

Almost surely, 2^136242209 is an apocalyptic number.

It is an amenable number.

136242209 is a deficient number, since it is larger than the sum of its proper divisors (23395).

136242209 is a wasteful number, since it uses less digits than its factorization.

136242209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23394.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 136242209 is about 11672.2837953847. The cubic root of 136242209 is about 514.5614250878.

The spelling of 136242209 in words is "one hundred thirty-six million, two hundred forty-two thousand, two hundred nine".