1287428 has 12 divisors (see below), whose sum is σ = 2284380. Its totient is φ = 634752.

The previous prime is 1287401. The next prime is 1287431. The reversal of 1287428 is 8247821.

It can be written as a sum of positive squares in 2 ways, for example, as 369664 + 917764 = 608^2 + 958^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1287394 and 1287403.

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, 1913 + ... + 2496.

It is an arithmetic number, because the mean of its divisors is an integer number (190365).

2^1287428 is an apocalyptic number.

It is an amenable number.

1287428 is a deficient number, since it is larger than the sum of its proper divisors (996952).

1287428 is a wasteful number, since it uses less digits than its factorization.

1287428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4486 (or 4484 counting only the distinct ones).

The product of its digits is 7168, while the sum is 32.

The square root of 1287428 is about 1134.6488443567. The cubic root of 1287428 is about 108.7863277586.

The spelling of 1287428 in words is "one million, two hundred eighty-seven thousand, four hundred twenty-eight".