227821409 has 2 divisors, whose sum is σ = 227821410. Its totient is φ = 227821408.

The previous prime is 227821367. The next prime is 227821411. The reversal of 227821409 is 904128722.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 215062225 + 12759184 = 14665^2 + 3572^2 .

It is a cyclic number.

It is not a de Polignac number, because 227821409 - 2¹⁶ = 227755873 is a prime.

Together with 227821411, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (227820409) 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 as a sum of consecutive naturals, namely, 113910704 + 113910705.

It is an arithmetic number, because the mean of its divisors is an integer number (113910705).

Almost surely, 2^227821409 is an apocalyptic number.

It is an amenable number.

227821409 is a deficient number, since it is larger than the sum of its proper divisors (1).

227821409 is an equidigital number, since it uses as much as digits as its factorization.

227821409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 227821409 is about 15093.7539730844. The cubic root of 227821409 is about 610.7519250281.

The spelling of 227821409 in words is "two hundred twenty-seven million, eight hundred twenty-one thousand, four hundred nine".