13689521 has 4 divisors (see below), whose sum is σ = 13719552. Its totient is φ = 13659492.

The previous prime is 13689517. The next prime is 13689541. The reversal of 13689521 is 12598631.

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 not a de Polignac number, because 13689521 - 2² = 13689517 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (13689541) 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 3 ways as a sum of consecutive naturals, for example, 14321 + ... + 15246.

It is an arithmetic number, because the mean of its divisors is an integer number (3429888).

Almost surely, 2^13689521 is an apocalyptic number.

It is an amenable number.

13689521 is a deficient number, since it is larger than the sum of its proper divisors (30031).

13689521 is an equidigital number, since it uses as much as digits as its factorization.

13689521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30030.

The product of its digits is 12960, while the sum is 35.

The square root of 13689521 is about 3699.9352697041. The cubic root of 13689521 is about 239.2192277788.

The spelling of 13689521 in words is "thirteen million, six hundred eighty-nine thousand, five hundred twenty-one".