21000020112120 has 64 divisors (see below), whose sum is σ = 72000068958720. Its totient is φ = 4800004596864.

The previous prime is 21000020112083. The next prime is 21000020112277. The reversal of 21000020112120 is 2121102000012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21000020112096 and 21000020112105.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12500011132 + ... + 12500012811.

It is an arithmetic number, because the mean of its divisors is an integer number (1125001077480).

Almost surely, 2^{21000020112120} is an apocalyptic number.

21000020112120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21000020112120 is an abundant number, since it is smaller than the sum of its proper divisors (51000048846600).

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

21000020112120 is a wasteful number, since it uses less digits than its factorization.

21000020112120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25000023964 (or 25000023960 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21000020112120 its reverse (2121102000012), we get a palindrome (23121122112132).

The spelling of 21000020112120 in words is "twenty-one trillion, twenty million, one hundred twelve thousand, one hundred twenty".