20011223221 has 8 divisors (see below), whose sum is σ = 21928322304. Its totient is φ = 18110440320.

The previous prime is 20011223189. The next prime is 20011223231. The reversal of 20011223221 is 12232211002.

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 20011223221 - 2⁵ = 20011223189 is a prime.

It is a super-2 number, since 2×20011223221² (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 = 20011223195 and 20011223204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011223231) 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, 4076476 + ... + 4081381.

It is an arithmetic number, because the mean of its divisors is an integer number (2741040288).

Almost surely, 2^20011223221 is an apocalyptic number.

It is an amenable number.

20011223221 is a deficient number, since it is larger than the sum of its proper divisors (1917099083).

20011223221 is a wasteful number, since it uses less digits than its factorization.

20011223221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8158091.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 20011223221 its reverse (12232211002), we get a palindrome (32243434223).

The spelling of 20011223221 in words is "twenty billion, eleven million, two hundred twenty-three thousand, two hundred twenty-one".