11663605 has 4 divisors (see below), whose sum is σ = 13996332. Its totient is φ = 9330880.

The previous prime is 11663593. The next prime is 11663609. The reversal of 11663605 is 50636611.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50636611 = 2851 ⋅17761.

It can be written as a sum of positive squares in 2 ways, for example, as 6959044 + 4704561 = 2638^2 + 2169^2 .

It is not a de Polignac number, because 11663605 - 2¹⁵ = 11630837 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11663609) 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, 1166356 + ... + 1166365.

It is an arithmetic number, because the mean of its divisors is an integer number (3499083).

Almost surely, 2^11663605 is an apocalyptic number.

It is an amenable number.

11663605 is a deficient number, since it is larger than the sum of its proper divisors (2332727).

11663605 is an equidigital number, since it uses as much as digits as its factorization.

11663605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2332726.

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

The square root of 11663605 is about 3415.2020438036. The cubic root of 11663605 is about 226.7832289274.

The spelling of 11663605 in words is "eleven million, six hundred sixty-three thousand, six hundred five".