2011578581 has 4 divisors (see below), whose sum is σ = 2013177600. Its totient is φ = 2009979564.

The previous prime is 2011578577. The next prime is 2011578629. The reversal of 2011578581 is 1858751102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2011578581 - 2² = 2011578577 is a prime.

It is a super-2 number, since 2×2011578581² = 8092896775075947122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2011571581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 797621 + ... + 800138.

It is an arithmetic number, because the mean of its divisors is an integer number (503294400).

Almost surely, 2^2011578581 is an apocalyptic number.

It is an amenable number.

2011578581 is a deficient number, since it is larger than the sum of its proper divisors (1599019).

2011578581 is a wasteful number, since it uses less digits than its factorization.

2011578581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1599018.

The product of its (nonzero) digits is 22400, while the sum is 38.

The square root of 2011578581 is about 44850.6252018854. The cubic root of 2011578581 is about 1262.3477226526.

The spelling of 2011578581 in words is "two billion, eleven million, five hundred seventy-eight thousand, five hundred eighty-one".