1280987 has 2 divisors, whose sum is σ = 1280988. Its totient is φ = 1280986.

The previous prime is 1280969. The next prime is 1280989. The reversal of 1280987 is 7890821.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1280987 - 2¹⁶ = 1215451 is a prime.

Together with 1280989, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1280989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 640493 + 640494.

It is an arithmetic number, because the mean of its divisors is an integer number (640494).

2^1280987 is an apocalyptic number.

1280987 is a deficient number, since it is larger than the sum of its proper divisors (1).

1280987 is an equidigital number, since it uses as much as digits as its factorization.

1280987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8064, while the sum is 35.

The square root of 1280987 is about 1131.8069623394. The cubic root of 1280987 is about 108.6046050999.

The spelling of 1280987 in words is "one million, two hundred eighty thousand, nine hundred eighty-seven".