21020100010120 has 128 divisors (see below), whose sum is σ = 48152981923200. Its totient is φ = 8256959078400.

The previous prime is 21020100010109. The next prime is 21020100010123. The reversal of 21020100010120 is 2101000102012.

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 = 21020100010097 and 21020100010106.

It is not an unprimeable number, because it can be changed into a prime (21020100010123) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1084562830 + ... + 1084582210.

It is an arithmetic number, because the mean of its divisors is an integer number (376195171275).

Almost surely, 2^{21020100010120} is an apocalyptic number.

21020100010120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21020100010120 is an abundant number, since it is smaller than the sum of its proper divisors (27132881913080).

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

21020100010120 is a wasteful number, since it uses less digits than its factorization.

21020100010120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21639 (or 21635 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21020100010120 its reverse (2101000102012), we get a palindrome (23121100112132).

The spelling of 21020100010120 in words is "twenty-one trillion, twenty billion, one hundred million, ten thousand, one hundred twenty".