1289287 has 2 divisors, whose sum is σ = 1289288. Its totient is φ = 1289286.

The previous prime is 1289273. The next prime is 1289303. The reversal of 1289287 is 7829821.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1289287 - 2⁷ = 1289159 is a prime.

1289287 is a lucky number.

It is a plaindrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1289237) 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, 644643 + 644644.

It is an arithmetic number, because the mean of its divisors is an integer number (644644).

2^1289287 is an apocalyptic number.

1289287 is a deficient number, since it is larger than the sum of its proper divisors (1).

1289287 is an equidigital number, since it uses as much as digits as its factorization.

1289287 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16128, while the sum is 37.

The square root of 1289287 is about 1135.4677450285. The cubic root of 1289287 is about 108.8386637655.

It can be divided in two parts, 128928 and 7, that multiplied together give a triangular number (902496 = T₁₃₄₃).

The spelling of 1289287 in words is "one million, two hundred eighty-nine thousand, two hundred eighty-seven".