136689021 has 24 divisors (see below), whose sum is σ = 237523520. Its totient is φ = 73996416.

The previous prime is 136689001. The next prime is 136689031. The reversal of 136689021 is 120986631.

It is not a de Polignac number, because 136689021 - 2¹⁹ = 136164733 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136689001) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55900 + ... + 58293.

Almost surely, 2^136689021 is an apocalyptic number.

It is an amenable number.

136689021 is a deficient number, since it is larger than the sum of its proper divisors (100834499).

136689021 is a wasteful number, since it uses less digits than its factorization.

136689021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114225 (or 114222 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 136689021 is about 11691.4079990393. The cubic root of 136689021 is about 515.1233198254.

The spelling of 136689021 in words is "one hundred thirty-six million, six hundred eighty-nine thousand, twenty-one".