21111011220020 has 24 divisors (see below), whose sum is σ = 44477531143584. Its totient is φ = 8416898282016.

The previous prime is 21111011219999. The next prime is 21111011220041. The reversal of 21111011220020 is 2002211011112.

It is an interprime number because it is at equal distance from previous prime (21111011219999) and next prime (21111011220041).

It is a junction number, because it is equal to n+sod(n) for n = 21111011219977 and 21111011220004.

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, 1719131582 + ... + 1719143861.

It is an arithmetic number, because the mean of its divisors is an integer number (1853230464316).

Almost surely, 2^{21111011220020} is an apocalyptic number.

21111011220020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21111011220020 is an abundant number, since it is smaller than the sum of its proper divisors (23366519923564).

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

21111011220020 is a wasteful number, since it uses less digits than its factorization.

21111011220020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3438275759 (or 3438275757 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21111011220020 its reverse (2002211011112), we get a palindrome (23113222231132).

The spelling of 21111011220020 in words is "twenty-one trillion, one hundred eleven billion, eleven million, two hundred twenty thousand, twenty".