136813721 has 8 divisors (see below), whose sum is σ = 149576544. Its totient is φ = 124105120.

The previous prime is 136813709. The next prime is 136813751. The reversal of 136813721 is 127318631.

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

It is a cyclic number.

It is not a de Polignac number, because 136813721 - 2⁶ = 136813657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (136813751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8180 + ... + 18453.

It is an arithmetic number, because the mean of its divisors is an integer number (18697068).

Almost surely, 2^136813721 is an apocalyptic number.

136813721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

136813721 is a deficient number, since it is larger than the sum of its proper divisors (12762823).

136813721 is a wasteful number, since it uses less digits than its factorization.

136813721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27111.

The product of its digits is 6048, while the sum is 32.

The square root of 136813721 is about 11696.7397594372. The cubic root of 136813721 is about 515.2799194643.

The spelling of 136813721 in words is "one hundred thirty-six million, eight hundred thirteen thousand, seven hundred twenty-one".