1391867 has 4 divisors (see below), whose sum is σ = 1424280. Its totient is φ = 1359456.

The previous prime is 1391861. The next prime is 1391893. The reversal of 1391867 is 7681931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7681931 = 23 ⋅333997.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1391867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1391861) 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, 16142 + ... + 16227.

It is an arithmetic number, because the mean of its divisors is an integer number (356070).

2^1391867 is an apocalyptic number.

1391867 is a deficient number, since it is larger than the sum of its proper divisors (32413).

1391867 is an equidigital number, since it uses as much as digits as its factorization.

1391867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32412.

The product of its digits is 9072, while the sum is 35.

The square root of 1391867 is about 1179.7741309251. The cubic root of 1391867 is about 111.6518472450.

Subtracting 1391867 from its reverse (7681931), we obtain a square (6290064 = 2508²).

The spelling of 1391867 in words is "one million, three hundred ninety-one thousand, eight hundred sixty-seven".