2013728581 has 2 divisors, whose sum is σ = 2013728582. Its totient is φ = 2013728580.

The previous prime is 2013728543. The next prime is 2013728609. The reversal of 2013728581 is 1858273102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1347624100 + 666104481 = 36710^2 + 25809^2 .

It is a cyclic number.

It is not a de Polignac number, because 2013728581 - 2⁹ = 2013728069 is a prime.

It is a super-2 number, since 2×2013728581² = 8110205595872547122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2013728581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2013728531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1006864290 + 1006864291.

It is an arithmetic number, because the mean of its divisors is an integer number (1006864291).

Almost surely, 2^2013728581 is an apocalyptic number.

It is an amenable number.

2013728581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2013728581 is an equidigital number, since it uses as much as digits as its factorization.

2013728581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26880, while the sum is 37.

The square root of 2013728581 is about 44874.5872515837. The cubic root of 2013728581 is about 1262.7973001249.

The spelling of 2013728581 in words is "two billion, thirteen million, seven hundred twenty-eight thousand, five hundred eighty-one".