136556621 has 8 divisors (see below), whose sum is σ = 143661600. Its totient is φ = 129611440.

The previous prime is 136556599. The next prime is 136556639. The reversal of 136556621 is 126655631.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 136556621 - 2¹⁰ = 136555597 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 (136556671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38195 + ... + 41616.

It is an arithmetic number, because the mean of its divisors is an integer number (17957700).

Almost surely, 2^136556621 is an apocalyptic number.

It is an amenable number.

136556621 is a deficient number, since it is larger than the sum of its proper divisors (7104979).

136556621 is an equidigital number, since it uses as much as digits as its factorization.

136556621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79899.

The product of its digits is 32400, while the sum is 35.

The square root of 136556621 is about 11685.7443494199. The cubic root of 136556621 is about 514.9569461605.

The spelling of 136556621 in words is "one hundred thirty-six million, five hundred fifty-six thousand, six hundred twenty-one".