11656621 has 4 divisors (see below), whose sum is σ = 11717212. Its totient is φ = 11596032.

The previous prime is 11656583. The next prime is 11656627. The reversal of 11656621 is 12665611.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12665611 = 7 ⋅1809373.

It can be written as a sum of positive squares in 2 ways, for example, as 2722500 + 8934121 = 1650^2 + 2989^2 .

It is a cyclic number.

It is not a de Polignac number, because 11656621 - 2⁹ = 11656109 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 11656621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11656627) 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, 30006 + ... + 30391.

It is an arithmetic number, because the mean of its divisors is an integer number (2929303).

Almost surely, 2^11656621 is an apocalyptic number.

It is an amenable number.

11656621 is a deficient number, since it is larger than the sum of its proper divisors (60591).

11656621 is an equidigital number, since it uses as much as digits as its factorization.

11656621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60590.

The product of its digits is 2160, while the sum is 28.

The square root of 11656621 is about 3414.1794036049. The cubic root of 11656621 is about 226.7379550375.

The spelling of 11656621 in words is "eleven million, six hundred fifty-six thousand, six hundred twenty-one".