136515857 has 4 divisors (see below), whose sum is σ = 137305140. Its totient is φ = 135726576.

The previous prime is 136515809. The next prime is 136515859. The reversal of 136515857 is 758515631.

It is a Cunningham number, because it is equal to 11684²+1.

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 124188736 + 12327121 = 11144^2 + 3511^2 .

It is a cyclic number.

It is not a de Polignac number, because 136515857 - 2⁸ = 136515601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (136515859) 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, 394382 + ... + 394727.

It is an arithmetic number, because the mean of its divisors is an integer number (34326285).

Almost surely, 2^136515857 is an apocalyptic number.

It is an amenable number.

136515857 is a deficient number, since it is larger than the sum of its proper divisors (789283).

136515857 is an equidigital number, since it uses as much as digits as its factorization.

136515857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 789282.

The product of its digits is 126000, while the sum is 41.

The square root of 136515857 is about 11684.0000427936. Note that the first 4 decimals coincide. The cubic root of 136515857 is about 514.9057005211.

The spelling of 136515857 in words is "one hundred thirty-six million, five hundred fifteen thousand, eight hundred fifty-seven".