21002020122222 has 24 divisors (see below), whose sum is σ = 48181104986976. Its totient is φ = 6588869057856.

The previous prime is 21002020122221. The next prime is 21002020122229. The reversal of 21002020122222 is 22222102020012.

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 = 21002020122195 and 21002020122204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002020122221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34317026038 + ... + 34317026649.

It is an arithmetic number, because the mean of its divisors is an integer number (2007546041124).

Almost surely, 2^{21002020122222} is an apocalyptic number.

21002020122222 is an abundant number, since it is smaller than the sum of its proper divisors (27179084864754).

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

21002020122222 is a wasteful number, since it uses less digits than its factorization.

21002020122222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68634052712 (or 68634052709 counting only the distinct ones).

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

Adding to 21002020122222 its reverse (22222102020012), we get a palindrome (43224122142234).

The spelling of 21002020122222 in words is "twenty-one trillion, two billion, twenty million, one hundred twenty-two thousand, two hundred twenty-two".