1286638 has 8 divisors (see below), whose sum is σ = 1982232. Its totient is φ = 625896.

The previous prime is 1286633. The next prime is 1286641. The reversal of 1286638 is 8366821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1286633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8620 + ... + 8767.

It is an arithmetic number, because the mean of its divisors is an integer number (247779).

2^1286638 is an apocalyptic number.

1286638 is a deficient number, since it is larger than the sum of its proper divisors (695594).

1286638 is a wasteful number, since it uses less digits than its factorization.

1286638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17426.

The product of its digits is 13824, while the sum is 34.

The square root of 1286638 is about 1134.3006656086. The cubic root of 1286638 is about 108.7640718128.

The spelling of 1286638 in words is "one million, two hundred eighty-six thousand, six hundred thirty-eight".