136805287 has 4 divisors (see below), whose sum is σ = 137402920. Its totient is φ = 136207656.

The previous prime is 136805281. The next prime is 136805299. The reversal of 136805287 is 782508631.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 782508631 = 727 ⋅1076353.

It is a cyclic number.

It is not a de Polignac number, because 136805287 - 2⁷ = 136805159 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 (136805281) 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, 298473 + ... + 298930.

It is an arithmetic number, because the mean of its divisors is an integer number (34350730).

Almost surely, 2^136805287 is an apocalyptic number.

136805287 is a deficient number, since it is larger than the sum of its proper divisors (597633).

136805287 is an equidigital number, since it uses as much as digits as its factorization.

136805287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 597632.

The product of its (nonzero) digits is 80640, while the sum is 40.

The square root of 136805287 is about 11696.3792260682. The cubic root of 136805287 is about 515.2693309548.

The spelling of 136805287 in words is "one hundred thirty-six million, eight hundred five thousand, two hundred eighty-seven".