20111222221 has 8 divisors (see below), whose sum is σ = 20623636800. Its totient is φ = 19605173280.

The previous prime is 20111222203. The next prime is 20111222233. The reversal of 20111222221 is 12222211102.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20111222221 - 2⁵ = 20111222189 is a prime.

It is a super-2 number, since 2×20111222221² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20111222195 and 20111222204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20111222251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1585011 + ... + 1597648.

It is an arithmetic number, because the mean of its divisors is an integer number (2577954600).

Almost surely, 2^20111222221 is an apocalyptic number.

It is an amenable number.

20111222221 is a deficient number, since it is larger than the sum of its proper divisors (512414579).

20111222221 is an equidigital number, since it uses as much as digits as its factorization.

20111222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3182819.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 20111222221 its reverse (12222211102), we get a palindrome (32333433323).

The spelling of 20111222221 in words is "twenty billion, one hundred eleven million, two hundred twenty-two thousand, two hundred twenty-one".