1278321 has 8 divisors (see below), whose sum is σ = 1859424. Its totient is φ = 774720.

The previous prime is 1278289. The next prime is 1278323. The reversal of 1278321 is 1238721.

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

It is not a de Polignac number, because 1278321 - 2⁵ = 1278289 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 1278291 and 1278300.

It is not an unprimeable number, because it can be changed into a prime (1278323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19336 + ... + 19401.

It is an arithmetic number, because the mean of its divisors is an integer number (232428).

2^1278321 is an apocalyptic number.

1278321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1278321 is a deficient number, since it is larger than the sum of its proper divisors (581103).

1278321 is a wasteful number, since it uses less digits than its factorization.

1278321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38751.

The product of its digits is 672, while the sum is 24.

The square root of 1278321 is about 1130.6285862298. The cubic root of 1278321 is about 108.5292098580.

It can be divided in two parts, 127 and 8321, that added together give a palindrome (8448).

The spelling of 1278321 in words is "one million, two hundred seventy-eight thousand, three hundred twenty-one".