22021220021 has 4 divisors (see below), whose sum is σ = 22024303200. Its totient is φ = 22018136844.

The previous prime is 22021219973. The next prime is 22021220029. The reversal of 22021220021 is 12002212022.

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 22021220021 - 2²² = 22017025717 is a prime.

It is a super-4 number, since 4×22021220021⁴ (a number of 42 digits) contains 4444 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22021219978 and 22021220005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22021220029) 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, 1530851 + ... + 1545168.

It is an arithmetic number, because the mean of its divisors is an integer number (5506075800).

Almost surely, 2^22021220021 is an apocalyptic number.

It is an amenable number.

22021220021 is a deficient number, since it is larger than the sum of its proper divisors (3083179).

22021220021 is an equidigital number, since it uses as much as digits as its factorization.

22021220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3083178.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 22021220021 its reverse (12002212022), we get a palindrome (34023432043).

The spelling of 22021220021 in words is "twenty-two billion, twenty-one million, two hundred twenty thousand, twenty-one".