221124257 has 2 divisors, whose sum is σ = 221124258. Its totient is φ = 221124256.

The previous prime is 221124251. The next prime is 221124263. The reversal of 221124257 is 752421122.

It is a balanced prime because it is at equal distance from previous prime (221124251) and next prime (221124263).

It can be written as a sum of positive squares in only one way, i.e., 220938496 + 185761 = 14864^2 + 431^2 .

It is a cyclic number.

It is not a de Polignac number, because 221124257 - 2¹² = 221120161 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (221124251) 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, 110562128 + 110562129.

It is an arithmetic number, because the mean of its divisors is an integer number (110562129).

Almost surely, 2^221124257 is an apocalyptic number.

It is an amenable number.

221124257 is a deficient number, since it is larger than the sum of its proper divisors (1).

221124257 is an equidigital number, since it uses as much as digits as its factorization.

221124257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2240, while the sum is 26.

The square root of 221124257 is about 14870.2473752120. The cubic root of 221124257 is about 604.7076492032.

Adding to 221124257 its reverse (752421122), we get a palindrome (973545379).

The spelling of 221124257 in words is "two hundred twenty-one million, one hundred twenty-four thousand, two hundred fifty-seven".