1278369 has 16 divisors (see below), whose sum is σ = 1915200. Its totient is φ = 842688.

The previous prime is 1278341. The next prime is 1278371. The reversal of 1278369 is 9638721.

It is not a de Polignac number, because 1278369 - 2⁵ = 1278337 is a prime.

It is a super-2 number, since 2×1278369² = 3268454600322, which contains 22 as substring.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1278379) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2842 + ... + 3260.

It is an arithmetic number, because the mean of its divisors is an integer number (119700).

2^1278369 is an apocalyptic number.

It is an amenable number.

1278369 is a deficient number, since it is larger than the sum of its proper divisors (636831).

1278369 is a wasteful number, since it uses less digits than its factorization.

1278369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541 (or 535 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 1278369 is about 1130.6498131606. The cubic root of 1278369 is about 108.5305682380.

The spelling of 1278369 in words is "one million, two hundred seventy-eight thousand, three hundred sixty-nine".