22011220021 has 4 divisors (see below), whose sum is σ = 25155680032. Its totient is φ = 18866760012.

The previous prime is 22011220013. The next prime is 22011220051. The reversal of 22011220021 is 12002211022.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 22011220021 - 2³ = 22011220013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 22011219983 and 22011220010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22011220051) 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, 1572229995 + ... + 1572230008.

It is an arithmetic number, because the mean of its divisors is an integer number (6288920008).

Almost surely, 2^22011220021 is an apocalyptic number.

It is an amenable number.

22011220021 is a deficient number, since it is larger than the sum of its proper divisors (3144460011).

22011220021 is an equidigital number, since it uses as much as digits as its factorization.

22011220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3144460010.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 22011220021 its reverse (12002211022), we get a palindrome (34013431043).

The spelling of 22011220021 in words is "twenty-two billion, eleven million, two hundred twenty thousand, twenty-one".