136401409 has 4 divisors (see below), whose sum is σ = 137752020. Its totient is φ = 135050800.

The previous prime is 136401389. The next prime is 136401427. The reversal of 136401409 is 904104631.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 110187009 + 26214400 = 10497^2 + 5120^2 .

It is a cyclic number.

It is not a de Polignac number, because 136401409 - 2¹³ = 136393217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (136401709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 675154 + ... + 675355.

It is an arithmetic number, because the mean of its divisors is an integer number (34438005).

Almost surely, 2^136401409 is an apocalyptic number.

It is an amenable number.

136401409 is a deficient number, since it is larger than the sum of its proper divisors (1350611).

136401409 is a wasteful number, since it uses less digits than its factorization.

136401409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1350610.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 136401409 is about 11679.1013781027. The cubic root of 136401409 is about 514.7617699806.

The spelling of 136401409 in words is "one hundred thirty-six million, four hundred one thousand, four hundred nine".