21043142120 has 192 divisors, whose sum is σ = 64706947200. Its totient is φ = 6054289920.

The previous prime is 21043142059. The next prime is 21043142137. The reversal of 21043142120 is 2124134012.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 21043142092 and 21043142101.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 242741 + ... + 317819.

It is an arithmetic number, because the mean of its divisors is an integer number (337015350).

Almost surely, 2^21043142120 is an apocalyptic number.

21043142120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21043142120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32353473600).

21043142120 is an abundant number, since it is smaller than the sum of its proper divisors (43663805080).

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

21043142120 is a wasteful number, since it uses less digits than its factorization.

21043142120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75128 (or 75117 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21043142120 its reverse (2124134012), we get a palindrome (23167276132).

The spelling of 21043142120 in words is "twenty-one billion, forty-three million, one hundred forty-two thousand, one hundred twenty".