1220489 has 2 divisors, whose sum is σ = 1220490. Its totient is φ = 1220488.

The previous prime is 1220437. The next prime is 1220491. The reversal of 1220489 is 9840221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1177225 + 43264 = 1085^2 + 208^2 .

It is an emirp because it is prime and its reverse (9840221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1220489 - 2¹² = 1216393 is a prime.

Together with 1220491, it forms a pair of twin primes.

It is a Chen prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (1220689) 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, 610244 + 610245.

It is an arithmetic number, because the mean of its divisors is an integer number (610245).

2^1220489 is an apocalyptic number.

It is an amenable number.

1220489 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220489 is an equidigital number, since it uses as much as digits as its factorization.

1220489 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 1220489 is about 1104.7574394409. The cubic root of 1220489 is about 106.8672473658.

The spelling of 1220489 in words is "one million, two hundred twenty thousand, four hundred eighty-nine".