22121100221 has 4 divisors (see below), whose sum is σ = 24132109344. Its totient is φ = 20110091100.

The previous prime is 22121100217. The next prime is 22121100223. The reversal of 22121100221 is 12200112122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 22121100221 - 2² = 22121100217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22121100196 and 22121100205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22121100223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1005504545 + ... + 1005504566.

It is an arithmetic number, because the mean of its divisors is an integer number (6033027336).

Almost surely, 2^22121100221 is an apocalyptic number.

It is an amenable number.

22121100221 is a deficient number, since it is larger than the sum of its proper divisors (2011009123).

22121100221 is a wasteful number, since it uses less digits than its factorization.

22121100221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2011009122.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 22121100221 its reverse (12200112122), we get a palindrome (34321212343).

The spelling of 22121100221 in words is "twenty-two billion, one hundred twenty-one million, one hundred thousand, two hundred twenty-one".