1287109 has 2 divisors, whose sum is σ = 1287110. Its totient is φ = 1287108.

The previous prime is 1287101. The next prime is 1287131. The reversal of 1287109 is 9017821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 956484 + 330625 = 978^2 + 575^2 .

It is an emirp because it is prime and its reverse (9017821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1287109 - 2³ = 1287101 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1287101) 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, 643554 + 643555.

It is an arithmetic number, because the mean of its divisors is an integer number (643555).

2^1287109 is an apocalyptic number.

It is an amenable number.

1287109 is a deficient number, since it is larger than the sum of its proper divisors (1).

1287109 is an equidigital number, since it uses as much as digits as its factorization.

1287109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 1287109 is about 1134.5082635221. The cubic root of 1287109 is about 108.7773419603. Note that the first 3 decimals are identical.

The spelling of 1287109 in words is "one million, two hundred eighty-seven thousand, one hundred nine".