1002002012020 has 72 divisors (see below), whose sum is σ = 2203418831544. Its totient is φ = 382609903104.

The previous prime is 1002002012009. The next prime is 1002002012021. The reversal of 1002002012020 is 202102002001.

It can be written as a sum of positive squares in 12 ways, for example, as 71637593104 + 930364418916 = 267652^2 + 964554^2 .

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 = 1002002011988 and 1002002012006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1002002012021) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1105894 + ... + 1796386.

It is an arithmetic number, because the mean of its divisors is an integer number (30603039327).

Almost surely, 2^{1002002012020} is an apocalyptic number.

1002002012020 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 1002002012020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1101709415772).

1002002012020 is an abundant number, since it is smaller than the sum of its proper divisors (1201416819524).

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

1002002012020 is a wasteful number, since it uses less digits than its factorization.

1002002012020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690629 (or 690590 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 1002002012020 its reverse (202102002001), we get a palindrome (1204104014021).

The spelling of 1002002012020 in words is "one trillion, two billion, two million, twelve thousand, twenty".