1211281 has 2 divisors, whose sum is σ = 1211282. Its totient is φ = 1211280.

The previous prime is 1211279. The next prime is 1211303. The reversal of 1211281 is 1821121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 919681 + 291600 = 959^2 + 540^2 .

It is an emirp because it is prime and its reverse (1821121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1211281 - 2¹ = 1211279 is a prime.

It is a super-2 number, since 2×1211281² = 2934403321922, which contains 22 as substring.

Together with 1211279, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1211261) 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, 605640 + 605641.

It is an arithmetic number, because the mean of its divisors is an integer number (605641).

2^1211281 is an apocalyptic number.

It is an amenable number.

1211281 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211281 is an equidigital number, since it uses as much as digits as its factorization.

1211281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32, while the sum is 16.

The square root of 1211281 is about 1100.5821186990. The cubic root of 1211281 is about 106.5978147245.

The spelling of 1211281 in words is "one million, two hundred eleven thousand, two hundred eighty-one".