1285289 has 2 divisors, whose sum is σ = 1285290. Its totient is φ = 1285288.

The previous prime is 1285283. The next prime is 1285301. The reversal of 1285289 is 9825821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1283689 + 1600 = 1133^2 + 40^2 .

It is an emirp because it is prime and its reverse (9825821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1285289 - 2¹² = 1281193 is a prime.

It is not a weakly prime, because it can be changed into another prime (1285283) by changing a digit.

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

It is an upside-down number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 642644 + 642645.

It is an arithmetic number, because the mean of its divisors is an integer number (642645).

2^1285289 is an apocalyptic number.

It is an amenable number.

1285289 is a deficient number, since it is larger than the sum of its proper divisors (1).

1285289 is an equidigital number, since it uses as much as digits as its factorization.

1285289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11520, while the sum is 35.

The square root of 1285289 is about 1133.7058701445. The cubic root of 1285289 is about 108.7260466027.

It can be divided in two parts, 12852 and 89, that multiplied together give a triangular number (1143828 = T₁₅₁₂).

The spelling of 1285289 in words is "one million, two hundred eighty-five thousand, two hundred eighty-nine".