135842409 has 24 divisors (see below), whose sum is σ = 203603400. Its totient is φ = 87171840.

The previous prime is 135842387. The next prime is 135842411. The reversal of 135842409 is 904248531.

It can be written as a sum of positive squares in 4 ways, for example, as 632025 + 135210384 = 795^2 + 11628^2 .

It is not a de Polignac number, because 135842409 - 2²¹ = 133745257 is a prime.

It is not an unprimeable number, because it can be changed into a prime (135842479) 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 23 ways as a sum of consecutive naturals, for example, 119757 + ... + 120885.

It is an arithmetic number, because the mean of its divisors is an integer number (8483475).

Almost surely, 2^135842409 is an apocalyptic number.

It is an amenable number.

135842409 is a deficient number, since it is larger than the sum of its proper divisors (67760991).

135842409 is a wasteful number, since it uses less digits than its factorization.

135842409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1625 (or 1622 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 135842409 is about 11655.1451728410. The cubic root of 135842409 is about 514.0576085965.

The spelling of 135842409 in words is "one hundred thirty-five million, eight hundred forty-two thousand, four hundred nine".