1278839 has 2 divisors, whose sum is σ = 1278840. Its totient is φ = 1278838.

The previous prime is 1278817. The next prime is 1278857. The reversal of 1278839 is 9388721.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1278839 - 2⁸ = 1278583 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1278899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639419 + 639420.

It is an arithmetic number, because the mean of its divisors is an integer number (639420).

2^1278839 is an apocalyptic number.

1278839 is a deficient number, since it is larger than the sum of its proper divisors (1).

1278839 is an equidigital number, since it uses as much as digits as its factorization.

1278839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 38.

The square root of 1278839 is about 1130.8576391394. The cubic root of 1278839 is about 108.5438672456.

Adding to 1278839 its product of digits (24192), we get a palindrome (1303031).

The spelling of 1278839 in words is "one million, two hundred seventy-eight thousand, eight hundred thirty-nine".