1316728581 has 16 divisors (see below), whose sum is σ = 2006957568. Its totient is φ = 752223600.

The previous prime is 1316728579. The next prime is 1316728603. The reversal of 1316728581 is 1858276131.

It is not a de Polignac number, because 1316728581 - 2¹ = 1316728579 is a prime.

It is a super-2 number, since 2×1316728581² = 3467548312044547122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1316728561) 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, 135826 + ... + 145196.

It is an arithmetic number, because the mean of its divisors is an integer number (125434848).

Almost surely, 2^1316728581 is an apocalyptic number.

It is an amenable number.

1316728581 is a deficient number, since it is larger than the sum of its proper divisors (690228987).

1316728581 is an equidigital number, since it uses as much as digits as its factorization.

1316728581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16072.

The product of its digits is 80640, while the sum is 42.

The square root of 1316728581 is about 36286.7548976207. The cubic root of 1316728581 is about 1096.0543436234.

The spelling of 1316728581 in words is "one billion, three hundred sixteen million, seven hundred twenty-eight thousand, five hundred eighty-one".