1317520720 has 40 divisors (see below), whose sum is σ = 3080193480. Its totient is φ = 524090880.

The previous prime is 1317520703. The next prime is 1317520747. The reversal of 1317520720 is 270257131.

It can be written as a sum of positive squares in 4 ways, for example, as 11999296 + 1305521424 = 3464^2 + 36132^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31015 + ... + 59974.

It is an arithmetic number, because the mean of its divisors is an integer number (77004837).

Almost surely, 2^1317520720 is an apocalyptic number.

1317520720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1317520720 is an abundant number, since it is smaller than the sum of its proper divisors (1762672760).

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

1317520720 is a wasteful number, since it uses less digits than its factorization.

1317520720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91183 (or 91177 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 28.

The square root of 1317520720 is about 36297.6682446683. The cubic root of 1317520720 is about 1096.2740936298.

Adding to 1317520720 its reverse (270257131), we get a palindrome (1587777851).

The spelling of 1317520720 in words is "one billion, three hundred seventeen million, five hundred twenty thousand, seven hundred twenty".