21020110020020 has 24 divisors (see below), whose sum is σ = 44161007079168. Its totient is φ = 8404467620000.

The previous prime is 21020110019999. The next prime is 21020110020023. The reversal of 21020110020020 is 2002001102012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21020110019983 and 21020110020010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21020110020023) 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, 223476056 + ... + 223570095.

It is an arithmetic number, because the mean of its divisors is an integer number (1840041961632).

Almost surely, 2^{21020110020020} is an apocalyptic number.

21020110020020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21020110020020 is an abundant number, since it is smaller than the sum of its proper divisors (23140897059148).

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

21020110020020 is a wasteful number, since it uses less digits than its factorization.

21020110020020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 447048511 (or 447048509 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21020110020020 its reverse (2002001102012), we get a palindrome (23022111122032).

The spelling of 21020110020020 in words is "twenty-one trillion, twenty billion, one hundred ten million, twenty thousand, twenty".