11766221 has 4 divisors (see below), whose sum is σ = 12053244. Its totient is φ = 11479200.

The previous prime is 11766217. The next prime is 11766233. The reversal of 11766221 is 12266711.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12266711 = 479 ⋅25609.

It can be written as a sum of positive squares in 2 ways, for example, as 1590121 + 10176100 = 1261^2 + 3190^2 .

It is a cyclic number.

It is not a de Polignac number, because 11766221 - 2² = 11766217 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 (11766241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 143450 + ... + 143531.

It is an arithmetic number, because the mean of its divisors is an integer number (3013311).

Almost surely, 2^11766221 is an apocalyptic number.

It is an amenable number.

11766221 is a deficient number, since it is larger than the sum of its proper divisors (287023).

11766221 is an equidigital number, since it uses as much as digits as its factorization.

11766221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287022.

The product of its digits is 1008, while the sum is 26.

The square root of 11766221 is about 3430.1925601925. The cubic root of 11766221 is about 227.4463650078.

The spelling of 11766221 in words is "eleven million, seven hundred sixty-six thousand, two hundred twenty-one".