1318343521 has 16 divisors (see below), whose sum is σ = 1461341376. Its totient is φ = 1189188000.

The previous prime is 1318343513. The next prime is 1318343527. The reversal of 1318343521 is 1253438131.

It is a happy number.

It is not a de Polignac number, because 1318343521 - 2³ = 1318343513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1318343527) 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, 170581 + ... + 178141.

It is an arithmetic number, because the mean of its divisors is an integer number (91333836).

Almost surely, 2^1318343521 is an apocalyptic number.

1318343521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1318343521 is a deficient number, since it is larger than the sum of its proper divisors (142997855).

1318343521 is an equidigital number, since it uses as much as digits as its factorization.

1318343521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7725 (or 7703 counting only the distinct ones).

The product of its digits is 8640, while the sum is 31.

The square root of 1318343521 is about 36309.0005508276. Note that the first 3 decimals coincide. The cubic root of 1318343521 is about 1096.5022564461.

The spelling of 1318343521 in words is "one billion, three hundred eighteen million, three hundred forty-three thousand, five hundred twenty-one".