11780221 has 4 divisors (see below), whose sum is σ = 12030912. Its totient is φ = 11529532.

The previous prime is 11780207. The next prime is 11780227. The reversal of 11780221 is 12208711.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12208711 = 97 ⋅125863.

It is a cyclic number.

It is not a de Polignac number, because 11780221 - 2⁹ = 11779709 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11780192 and 11780201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11780227) 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, 125275 + ... + 125368.

It is an arithmetic number, because the mean of its divisors is an integer number (3007728).

Almost surely, 2^11780221 is an apocalyptic number.

It is an amenable number.

11780221 is a deficient number, since it is larger than the sum of its proper divisors (250691).

11780221 is an equidigital number, since it uses as much as digits as its factorization.

11780221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250690.

The product of its (nonzero) digits is 224, while the sum is 22.

The square root of 11780221 is about 3432.2326552843. The cubic root of 11780221 is about 227.5365380271.

Adding to 11780221 its reverse (12208711), we get a palindrome (23988932).

The spelling of 11780221 in words is "eleven million, seven hundred eighty thousand, two hundred twenty-one".