2111221221 has 16 divisors (see below), whose sum is σ = 3016742784. Its totient is φ = 1309898304.

The previous prime is 2111221219. The next prime is 2111221253. The reversal of 2111221221 is 1221221112.

It is not a de Polignac number, because 2111221221 - 2¹ = 2111221219 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2111221221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2111221921) 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, 410926 + ... + 416031.

It is an arithmetic number, because the mean of its divisors is an integer number (188546424).

Almost surely, 2^2111221221 is an apocalyptic number.

It is an amenable number.

2111221221 is a deficient number, since it is larger than the sum of its proper divisors (905521563).

2111221221 is a wasteful number, since it uses less digits than its factorization.

2111221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 827020.

The product of its digits is 32, while the sum is 15.

The square root of 2111221221 is about 45948.0273896497. The cubic root of 2111221221 is about 1282.8560130922.

Adding to 2111221221 its reverse (1221221112), we get a palindrome (3332442333).

The spelling of 2111221221 in words is "two billion, one hundred eleven million, two hundred twenty-one thousand, two hundred twenty-one".