21010200020020 has 24 divisors (see below), whose sum is σ = 44198690503968. Its totient is φ = 8389361824800.

The previous prime is 21010200020003. The next prime is 21010200020071. The reversal of 21010200020020 is 2002000201012.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 21010200019979 and 21010200020006.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 919874746 + ... + 919897585.

It is an arithmetic number, because the mean of its divisors is an integer number (1841612104332).

Almost surely, 2^{21010200020020} is an apocalyptic number.

21010200020020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21010200020020 is an abundant number, since it is smaller than the sum of its proper divisors (23188490483948).

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

21010200020020 is a wasteful number, since it uses less digits than its factorization.

21010200020020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1839772911 (or 1839772909 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 21010200020020 its reverse (2002000201012), we get a palindrome (23012200221032).

The spelling of 21010200020020 in words is "twenty-one trillion, ten billion, two hundred million, twenty thousand, twenty".