1318731 has 4 divisors (see below), whose sum is σ = 1758312. Its totient is φ = 879152.

The previous prime is 1318729. The next prime is 1318739. The reversal of 1318731 is 1378131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1378131 = 3 ⋅459377.

It is a cyclic number.

It is not a de Polignac number, because 1318731 - 2¹ = 1318729 is a prime.

It is a super-2 number, since 2×1318731² = 3478102900722, which contains 22 as substring.

It is a D-number.

1318731 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1318739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 219786 + ... + 219791.

It is an arithmetic number, because the mean of its divisors is an integer number (439578).

2^1318731 is an apocalyptic number.

1318731 is a deficient number, since it is larger than the sum of its proper divisors (439581).

1318731 is an equidigital number, since it uses as much as digits as its factorization.

1318731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439580.

The product of its digits is 504, while the sum is 24.

The square root of 1318731 is about 1148.3601351492. The cubic root of 1318731 is about 109.6609671540.

The spelling of 1318731 in words is "one million, three hundred eighteen thousand, seven hundred thirty-one".