1218281 has 2 divisors, whose sum is σ = 1218282. Its totient is φ = 1218280.

The previous prime is 1218277. The next prime is 1218307. The reversal of 1218281 is 1828121.

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., 1210000 + 8281 = 1100^2 + 91^2 .

It is an emirp because it is prime and its reverse (1828121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1218281 - 2² = 1218277 is a prime.

It is a super-2 number, since 2×1218281² = 2968417189922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1218211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609140 + 609141.

It is an arithmetic number, because the mean of its divisors is an integer number (609141).

2^1218281 is an apocalyptic number.

It is an amenable number.

1218281 is a deficient number, since it is larger than the sum of its proper divisors (1).

1218281 is an equidigital number, since it uses as much as digits as its factorization.

1218281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 256, while the sum is 23.

The square root of 1218281 is about 1103.7576726800. The cubic root of 1218281 is about 106.8027635620.

It can be divided in two parts, 121 and 8281, that multiplied together give a palindrome (1002001).

The spelling of 1218281 in words is "one million, two hundred eighteen thousand, two hundred eighty-one".