21221222022 has 128 divisors (see below), whose sum is σ = 63317560320. Its totient is φ = 5087992320.

The previous prime is 21221221997. The next prime is 21221222023. The reversal of 21221222022 is 22022212212.

21221222022 is a `hidden beast` number, since 212 + 212 + 220 + 22 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21221221986 and 21221222004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221222023) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 142243 + ... + 250350.

It is an arithmetic number, because the mean of its divisors is an integer number (494668440).

Almost surely, 2^21221222022 is an apocalyptic number.

21221222022 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21221222022 is an abundant number, since it is smaller than the sum of its proper divisors (42096338298).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21221222022 is a wasteful number, since it uses less digits than its factorization.

21221222022 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392635 (or 392629 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 21221222022 its reverse (22022212212), we get a palindrome (43243434234).

The spelling of 21221222022 in words is "twenty-one billion, two hundred twenty-one million, two hundred twenty-two thousand, twenty-two".