21221222000020 has 24 divisors (see below), whose sum is σ = 50930932800384. Its totient is φ = 7275847542816.

The previous prime is 21221221999961. The next prime is 21221222000023. The reversal of 21221222000020 is 2000022212212.

It is a junction number, because it is equal to n+sod(n) for n = 21221221999958 and 21221222000003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221222000023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75790078432 + ... + 75790078711.

It is an arithmetic number, because the mean of its divisors is an integer number (2122122200016).

Almost surely, 2^{21221222000020} is an apocalyptic number.

21221222000020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221222000020 is an abundant number, since it is smaller than the sum of its proper divisors (29709710800364).

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

21221222000020 is a wasteful number, since it uses less digits than its factorization.

21221222000020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151580157159 (or 151580157157 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 21221222000020 its reverse (2000022212212), we get a palindrome (23221244212232).

The spelling of 21221222000020 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twenty-two million, twenty", and thus it is an aban number.