11157221 has 2 divisors, whose sum is σ = 11157222. Its totient is φ = 11157220.

The previous prime is 11157217. The next prime is 11157227. The reversal of 11157221 is 12275111.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8940100 + 2217121 = 2990^2 + 1489^2 .

It is an emirp because it is prime and its reverse (12275111) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11157221 - 2² = 11157217 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 11157193 and 11157202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11157227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5578610 + 5578611.

It is an arithmetic number, because the mean of its divisors is an integer number (5578611).

Almost surely, 2^11157221 is an apocalyptic number.

It is an amenable number.

11157221 is a deficient number, since it is larger than the sum of its proper divisors (1).

11157221 is an equidigital number, since it uses as much as digits as its factorization.

11157221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 140, while the sum is 20.

The square root of 11157221 is about 3340.2426558560. The cubic root of 11157221 is about 223.4525654764.

The spelling of 11157221 in words is "eleven million, one hundred fifty-seven thousand, two hundred twenty-one".