1287938 has 4 divisors (see below), whose sum is σ = 1931910. Its totient is φ = 643968.

The previous prime is 1287917. The next prime is 1287947. The reversal of 1287938 is 8397821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8397821 = 113 ⋅74317.

It can be written as a sum of positive squares in only one way, i.e., 744769 + 543169 = 863^2 + 737^2 .

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321983 + ... + 321986.

2^1287938 is an apocalyptic number.

1287938 is a deficient number, since it is larger than the sum of its proper divisors (643972).

1287938 is an equidigital number, since it uses as much as digits as its factorization.

1287938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 643971.

The product of its digits is 24192, while the sum is 38.

The square root of 1287938 is about 1134.8735612393. The cubic root of 1287938 is about 108.8006906855.

It can be divided in two parts, 128 and 7938, that multiplied together give a square (1016064 = 1008²).

The spelling of 1287938 in words is "one million, two hundred eighty-seven thousand, nine hundred thirty-eight".