2011356861 has 4 divisors (see below), whose sum is σ = 2681809152. Its totient is φ = 1340904572.

The previous prime is 2011356821. The next prime is 2011356871. The reversal of 2011356861 is 1686531102.

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 2011356861 - 2⁶ = 2011356797 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2011356821) 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, 335226141 + ... + 335226146.

It is an arithmetic number, because the mean of its divisors is an integer number (670452288).

Almost surely, 2^2011356861 is an apocalyptic number.

It is an amenable number.

2011356861 is a deficient number, since it is larger than the sum of its proper divisors (670452291).

2011356861 is an equidigital number, since it uses as much as digits as its factorization.

2011356861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 670452290.

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 2011356861 is about 44848.1533733553. The cubic root of 2011356861 is about 1262.3013414964.

Adding to 2011356861 its reverse (1686531102), we get a palindrome (3697887963).

The spelling of 2011356861 in words is "two billion, eleven million, three hundred fifty-six thousand, eight hundred sixty-one".