1221239 has 2 divisors, whose sum is σ = 1221240. Its totient is φ = 1221238.

The previous prime is 1221223. The next prime is 1221247. The reversal of 1221239 is 9321221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221239 - 2⁴ = 1221223 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1221239.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221289) 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, 610619 + 610620.

It is an arithmetic number, because the mean of its divisors is an integer number (610620).

2^1221239 is an apocalyptic number.

1221239 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221239 is an equidigital number, since it uses as much as digits as its factorization.

1221239 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 216, while the sum is 20.

The square root of 1221239 is about 1105.0968283368. The cubic root of 1221239 is about 106.8891331355.

The spelling of 1221239 in words is "one million, two hundred twenty-one thousand, two hundred thirty-nine".