1317331638 has 24 divisors (see below), whose sum is σ = 3261964368. Its totient is φ = 376380432.

The previous prime is 1317331637. The next prime is 1317331663. The reversal of 1317331638 is 8361337131.

It is a happy number.

1317331638 is a `hidden beast` number, since 1 + 3 + 17 + 3 + 3 + 1 + 638 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1317331637) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5227381 + ... + 5227632.

It is an arithmetic number, because the mean of its divisors is an integer number (135915182).

Almost surely, 2^1317331638 is an apocalyptic number.

1317331638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1317331638 is an abundant number, since it is smaller than the sum of its proper divisors (1944632730).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1317331638 is a wasteful number, since it uses less digits than its factorization.

1317331638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10455028 (or 10455025 counting only the distinct ones).

The product of its digits is 27216, while the sum is 36.

The square root of 1317331638 is about 36295.0635486425. The cubic root of 1317331638 is about 1096.2216477462.

Adding to 1317331638 its reverse (8361337131), we get a palindrome (9678668769).

The spelling of 1317331638 in words is "one billion, three hundred seventeen million, three hundred thirty-one thousand, six hundred thirty-eight".