21421102232020 has 12 divisors (see below), whose sum is σ = 44984314687284. Its totient is φ = 8568440892800.

The previous prime is 21421102231993. The next prime is 21421102232027. The reversal of 21421102232020 is 2023220112412.

It can be written as a sum of positive squares in 2 ways, for example, as 4595715512644 + 16825386719376 = 2143762^2 + 4101876^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21421102231982 and 21421102232000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21421102232027) 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, 535527555781 + ... + 535527555820.

It is an arithmetic number, because the mean of its divisors is an integer number (3748692890607).

Almost surely, 2^{21421102232020} is an apocalyptic number.

21421102232020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21421102232020 is an abundant number, since it is smaller than the sum of its proper divisors (23563212455264).

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

21421102232020 is a wasteful number, since it uses less digits than its factorization.

21421102232020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1071055111610 (or 1071055111608 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 21421102232020 its reverse (2023220112412), we get a palindrome (23444322344432).

The spelling of 21421102232020 in words is "twenty-one trillion, four hundred twenty-one billion, one hundred two million, two hundred thirty-two thousand, twenty".