136639871 has 4 divisors (see below), whose sum is σ = 136667952. Its totient is φ = 136611792.

The previous prime is 136639861. The next prime is 136639879. The reversal of 136639871 is 178936631.

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 136639871 - 2⁶ = 136639807 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 (136639879) 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, 4646 + ... + 17171.

It is an arithmetic number, because the mean of its divisors is an integer number (34166988).

Almost surely, 2^136639871 is an apocalyptic number.

136639871 is a deficient number, since it is larger than the sum of its proper divisors (28081).

136639871 is an equidigital number, since it uses as much as digits as its factorization.

136639871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28080.

The product of its digits is 163296, while the sum is 44.

The square root of 136639871 is about 11689.3058390993. The cubic root of 136639871 is about 515.0615705442.

The spelling of 136639871 in words is "one hundred thirty-six million, six hundred thirty-nine thousand, eight hundred seventy-one".