221231027 has 2 divisors, whose sum is σ = 221231028. Its totient is φ = 221231026.

The previous prime is 221231009. The next prime is 221231033. The reversal of 221231027 is 720132122.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221231027 is a prime.

It is not a weakly prime, because it can be changed into another prime (221231077) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110615513 + 110615514.

It is an arithmetic number, because the mean of its divisors is an integer number (110615514).

Almost surely, 2^221231027 is an apocalyptic number.

221231027 is a deficient number, since it is larger than the sum of its proper divisors (1).

221231027 is an equidigital number, since it uses as much as digits as its factorization.

221231027 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 221231027 is about 14873.8369965520. The cubic root of 221231027 is about 604.8049613776.

Adding to 221231027 its reverse (720132122), we get a palindrome (941363149).

The spelling of 221231027 in words is "two hundred twenty-one million, two hundred thirty-one thousand, twenty-seven".