136684591 has 4 divisors (see below), whose sum is σ = 138925384. Its totient is φ = 134443800.

The previous prime is 136684567. The next prime is 136684619. The reversal of 136684591 is 195486631.

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

It is a cyclic number.

It is not a de Polignac number, because 136684591 - 2⁷ = 136684463 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136684501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1120305 + ... + 1120426.

It is an arithmetic number, because the mean of its divisors is an integer number (34731346).

Almost surely, 2^136684591 is an apocalyptic number.

136684591 is a deficient number, since it is larger than the sum of its proper divisors (2240793).

136684591 is an equidigital number, since it uses as much as digits as its factorization.

136684591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2240792.

The product of its digits is 155520, while the sum is 43.

The square root of 136684591 is about 11691.2185421367. The cubic root of 136684591 is about 515.1177548309.

The spelling of 136684591 in words is "one hundred thirty-six million, six hundred eighty-four thousand, five hundred ninety-one".