136213621 has 4 divisors (see below), whose sum is σ = 136242700. Its totient is φ = 136184544.

The previous prime is 136213589. The next prime is 136213633. The reversal of 136213621 is 126312631.

136213621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 126312631 = 31 ⋅4074601.

It can be written as a sum of positive squares in 2 ways, for example, as 53494596 + 82719025 = 7314^2 + 9095^2 .

It is a cyclic number.

It is not a de Polignac number, because 136213621 - 2⁵ = 136213589 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 (136213681) 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, 5736 + ... + 17473.

It is an arithmetic number, because the mean of its divisors is an integer number (34060675).

Almost surely, 2^136213621 is an apocalyptic number.

It is an amenable number.

136213621 is a deficient number, since it is larger than the sum of its proper divisors (29079).

136213621 is an equidigital number, since it uses as much as digits as its factorization.

136213621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29078.

The product of its digits is 1296, while the sum is 25.

The square root of 136213621 is about 11671.0591207482. The cubic root of 136213621 is about 514.5254320547.

The spelling of 136213621 in words is "one hundred thirty-six million, two hundred thirteen thousand, six hundred twenty-one".