1200021110020 has 144 divisors (see below), whose sum is σ = 2691874809792. Its totient is φ = 449271060480.

The previous prime is 1200021109999. The next prime is 1200021110023. The reversal of 1200021110020 is 200111200021.

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 = 1200021109979 and 1200021110006.

It is not an unprimeable number, because it can be changed into a prime (1200021110023) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1505672262 + ... + 1505673058.

It is an arithmetic number, because the mean of its divisors is an integer number (18693575068).

Almost surely, 2^{1200021110020} is an apocalyptic number.

1200021110020 is a gapful number since it is divisible by the number (10) 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 1200021110020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1345937404896).

1200021110020 is an abundant number, since it is smaller than the sum of its proper divisors (1491853699772).

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

1200021110020 is a wasteful number, since it uses less digits than its factorization.

1200021110020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1958 (or 1939 counting only the distinct ones).

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

Adding to 1200021110020 its reverse (200111200021), we get a palindrome (1400132310041).

Subtracting from 1200021110020 its reverse (200111200021), we obtain a palindrome (999909909999).

The spelling of 1200021110020 in words is "one trillion, two hundred billion, twenty-one million, one hundred ten thousand, twenty".