13785665 has 4 divisors (see below), whose sum is σ = 16542804. Its totient is φ = 11028528.

The previous prime is 13785649. The next prime is 13785677. The reversal of 13785665 is 56658731.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5895184 + 7890481 = 2428^2 + 2809^2 .

It is a cyclic number.

It is not a de Polignac number, because 13785665 - 2⁴ = 13785649 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1378562 + ... + 1378571.

It is an arithmetic number, because the mean of its divisors is an integer number (4135701).

Almost surely, 2^13785665 is an apocalyptic number.

It is an amenable number.

13785665 is a deficient number, since it is larger than the sum of its proper divisors (2757139).

13785665 is an equidigital number, since it uses as much as digits as its factorization.

13785665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2757138.

The product of its digits is 151200, while the sum is 41.

The square root of 13785665 is about 3712.9051967428. The cubic root of 13785665 is about 239.7779485534. Note that the first 3 decimals are identical.

The spelling of 13785665 in words is "thirteen million, seven hundred eighty-five thousand, six hundred sixty-five".