1287217 has 2 divisors, whose sum is σ = 1287218. Its totient is φ = 1287216.

The previous prime is 1287199. The next prime is 1287233. The reversal of 1287217 is 7127821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 767376 + 519841 = 876^2 + 721^2 .

It is a cyclic number.

It is not a de Polignac number, because 1287217 - 2¹¹ = 1285169 is a prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (1287817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 643608 + 643609.

It is an arithmetic number, because the mean of its divisors is an integer number (643609).

2^1287217 is an apocalyptic number.

It is an amenable number.

1287217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1287217 is an equidigital number, since it uses as much as digits as its factorization.

1287217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1568, while the sum is 28.

The square root of 1287217 is about 1134.5558602378. Note that the first 3 decimals coincide. The cubic root of 1287217 is about 108.7803843403.

The spelling of 1287217 in words is "one million, two hundred eighty-seven thousand, two hundred seventeen".