2122222221 has 16 divisors (see below), whose sum is σ = 3593180800. Its totient is φ = 1212698304.

The previous prime is 2122222199. The next prime is 2122222231. The reversal of 2122222221 is 1222222212.

It is not a de Polignac number, because 2122222221 - 2¹⁷ = 2122091149 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2122222194 and 2122222203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2122222231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5614156 + ... + 5614533.

It is an arithmetic number, because the mean of its divisors is an integer number (224573800).

Almost surely, 2^2122222221 is an apocalyptic number.

2122222221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2122222221 is a deficient number, since it is larger than the sum of its proper divisors (1470958579).

2122222221 is a wasteful number, since it uses less digits than its factorization.

2122222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11228705 (or 11228699 counting only the distinct ones).

The product of its digits is 256, while the sum is 18.

The square root of 2122222221 is about 46067.5831903520. The cubic root of 2122222221 is about 1285.0803587449.

Adding to 2122222221 its reverse (1222222212), we get a palindrome (3344444433).

Subtracting from 2122222221 its reverse (1222222212), we obtain a palindrome (900000009).

It can be divided in two parts, 2 and 122222221, that multiplied together give a palindrome (244444442).

The spelling of 2122222221 in words is "two billion, one hundred twenty-two million, two hundred twenty-two thousand, two hundred twenty-one".