1378667 has 4 divisors (see below), whose sum is σ = 1383096. Its totient is φ = 1374240.

The previous prime is 1378639. The next prime is 1378669. The reversal of 1378667 is 7668731.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1378667 - 2⁶ = 1378603 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1378667.

It is not an unprimeable number, because it can be changed into a prime (1378669) 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, 1709 + ... + 2382.

It is an arithmetic number, because the mean of its divisors is an integer number (345774).

2^1378667 is an apocalyptic number.

1378667 is a deficient number, since it is larger than the sum of its proper divisors (4429).

1378667 is an equidigital number, since it uses as much as digits as its factorization.

1378667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4428.

The product of its digits is 42336, while the sum is 38.

The square root of 1378667 is about 1174.1665128933. The cubic root of 1378667 is about 111.2977693269.

Subtracting from 1378667 its product of digits (42336), we obtain a palindrome (1336331).

Subtracting 1378667 from its reverse (7668731), we obtain a square (6290064 = 2508²).

The spelling of 1378667 in words is "one million, three hundred seventy-eight thousand, six hundred sixty-seven".