136613521 has 4 divisors (see below), whose sum is σ = 149032944. Its totient is φ = 124194100.

The previous prime is 136613507. The next prime is 136613549. The reversal of 136613521 is 125316631.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-136613521 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 136613521.

It is not an unprimeable number, because it can be changed into a prime (136611521) 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, 6209695 + ... + 6209716.

It is an arithmetic number, because the mean of its divisors is an integer number (37258236).

Almost surely, 2^136613521 is an apocalyptic number.

136613521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

136613521 is a deficient number, since it is larger than the sum of its proper divisors (12419423).

136613521 is a wasteful number, since it uses less digits than its factorization.

136613521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12419422.

The product of its digits is 3240, while the sum is 28.

The square root of 136613521 is about 11688.1786861769. The cubic root of 136613521 is about 515.0284597965.

The spelling of 136613521 in words is "one hundred thirty-six million, six hundred thirteen thousand, five hundred twenty-one".