2011000021 has 4 divisors (see below), whose sum is σ = 2060048844. Its totient is φ = 1961951200.

The previous prime is 2011000007. The next prime is 2011000081. The reversal of 2011000021 is 1200001102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 155975121 + 1855024900 = 12489^2 + 43070^2 .

It is a cyclic number.

It is not a de Polignac number, because 2011000021 - 2¹¹ = 2010997973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2010999968 and 2011000013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2011000001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24524350 + ... + 24524431.

It is an arithmetic number, because the mean of its divisors is an integer number (515012211).

Almost surely, 2^2011000021 is an apocalyptic number.

It is an amenable number.

2011000021 is a deficient number, since it is larger than the sum of its proper divisors (49048823).

2011000021 is an equidigital number, since it uses as much as digits as its factorization.

2011000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49048822.

The product of its (nonzero) digits is 4, while the sum is 7.

The square root of 2011000021 is about 44844.1748837015. The cubic root of 2011000021 is about 1262.2266877042.

Adding to 2011000021 its reverse (1200001102), we get a palindrome (3211001123).

The spelling of 2011000021 in words is "two billion, eleven million, twenty-one", and thus it is an aban number and an uban number.