1311397 has 4 divisors (see below), whose sum is σ = 1388556. Its totient is φ = 1234240.

The previous prime is 1311383. The next prime is 1311403. The reversal of 1311397 is 7931131.

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

It can be written as a sum of positive squares in 2 ways, for example, as 772641 + 538756 = 879^2 + 734^2 .

It is a cyclic number.

It is not a de Polignac number, because 1311397 - 2¹¹ = 1309349 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38554 + ... + 38587.

It is an arithmetic number, because the mean of its divisors is an integer number (347139).

2^1311397 is an apocalyptic number.

1311397 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

1311397 is a deficient number, since it is larger than the sum of its proper divisors (77159).

1311397 is an equidigital number, since it uses as much as digits as its factorization.

1311397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77158.

The product of its digits is 567, while the sum is 25.

The square root of 1311397 is about 1145.1624338931. The cubic root of 1311397 is about 109.4572993643.

The spelling of 1311397 in words is "one million, three hundred eleven thousand, three hundred ninety-seven".