2111289721 has 16 divisors (see below), whose sum is σ = 2271582144. Its totient is φ = 1955142144.

The previous prime is 2111289703. The next prime is 2111289749. The reversal of 2111289721 is 1279821112.

It is a cyclic number.

It is not a de Polignac number, because 2111289721 - 2¹⁷ = 2111158649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2111289221) 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, 577726 + ... + 581368.

It is an arithmetic number, because the mean of its divisors is an integer number (141973884).

Almost surely, 2^2111289721 is an apocalyptic number.

It is an amenable number.

2111289721 is a deficient number, since it is larger than the sum of its proper divisors (160292423).

2111289721 is a wasteful number, since it uses less digits than its factorization.

2111289721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4200.

The product of its digits is 4032, while the sum is 34.

The square root of 2111289721 is about 45948.7727910115. The cubic root of 2111289721 is about 1282.8698873190.

The spelling of 2111289721 in words is "two billion, one hundred eleven million, two hundred eighty-nine thousand, seven hundred twenty-one".