1286605 has 4 divisors (see below), whose sum is σ = 1543932. Its totient is φ = 1029280.

The previous prime is 1286587. The next prime is 1286617. The reversal of 1286605 is 5066821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5066821 = 41 ⋅123581.

It can be written as a sum of positive squares in 2 ways, for example, as 522729 + 763876 = 723^2 + 874^2 .

It is not a de Polignac number, because 1286605 - 2⁹ = 1286093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 128656 + ... + 128665.

It is an arithmetic number, because the mean of its divisors is an integer number (385983).

2^1286605 is an apocalyptic number.

It is an amenable number.

1286605 is a deficient number, since it is larger than the sum of its proper divisors (257327).

1286605 is an equidigital number, since it uses as much as digits as its factorization.

1286605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257326.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 1286605 is about 1134.2861191075. The cubic root of 1286605 is about 108.7631419358.

It can be divided in two parts, 1286 and 605, that added together give a triangular number (1891 = T₆₁).

The spelling of 1286605 in words is "one million, two hundred eighty-six thousand, six hundred five".