136673809 has 2 divisors, whose sum is σ = 136673810. Its totient is φ = 136673808.

The previous prime is 136673807. The next prime is 136673851. The reversal of 136673809 is 908376631.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 121440400 + 15233409 = 11020^2 + 3903^2 .

It is a cyclic number.

It is not a de Polignac number, because 136673809 - 2¹ = 136673807 is a prime.

Together with 136673807, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (136673807) 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 as a sum of consecutive naturals, namely, 68336904 + 68336905.

It is an arithmetic number, because the mean of its divisors is an integer number (68336905).

Almost surely, 2^136673809 is an apocalyptic number.

It is an amenable number.

136673809 is a deficient number, since it is larger than the sum of its proper divisors (1).

136673809 is an equidigital number, since it uses as much as digits as its factorization.

136673809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 163296, while the sum is 43.

The square root of 136673809 is about 11690.7574177211. The cubic root of 136673809 is about 515.1042099106.

The spelling of 136673809 in words is "one hundred thirty-six million, six hundred seventy-three thousand, eight hundred nine".