1000021012120 has 128 divisors (see below), whose sum is σ = 2571338649600. Its totient is φ = 347198252544.

The previous prime is 1000021012037. The next prime is 1000021012141. The reversal of 1000021012120 is 212101200001.

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 = 1000021012097 and 1000021012106.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2952 + ... + 1414231.

It is an arithmetic number, because the mean of its divisors is an integer number (20088583200).

Almost surely, 2^{1000021012120} is an apocalyptic number.

1000021012120 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 1000021012120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1285669324800).

1000021012120 is an abundant number, since it is smaller than the sum of its proper divisors (1571317637480).

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

1000021012120 is a wasteful number, since it uses less digits than its factorization.

1000021012120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1417289 (or 1417285 counting only the distinct ones).

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

Adding to 1000021012120 its reverse (212101200001), we get a palindrome (1212122212121).

The spelling of 1000021012120 in words is "one trillion, twenty-one million, twelve thousand, one hundred twenty".