1287445 has 4 divisors (see below), whose sum is σ = 1544940. Its totient is φ = 1029952.

The previous prime is 1287431. The next prime is 1287457. The reversal of 1287445 is 5447821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 289444 + 998001 = 538^2 + 999^2 .

It is a cyclic number.

It is not a de Polignac number, because 1287445 - 2¹¹ = 1285397 is a prime.

It is a nialpdrome in base 6.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128740 + ... + 128749.

It is an arithmetic number, because the mean of its divisors is an integer number (386235).

2^1287445 is an apocalyptic number.

It is an amenable number.

1287445 is a deficient number, since it is larger than the sum of its proper divisors (257495).

1287445 is an equidigital number, since it uses as much as digits as its factorization.

1287445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257494.

The product of its digits is 8960, while the sum is 31.

The square root of 1287445 is about 1134.6563356365. The cubic root of 1287445 is about 108.7868065839.

The spelling of 1287445 in words is "one million, two hundred eighty-seven thousand, four hundred forty-five".