1002000020 has 36 divisors (see below), whose sum is σ = 2447745300. Its totient is φ = 343542528.

The previous prime is 1002000001. The next prime is 1002000029. The reversal of 1002000020 is 200002001.

It can be written as a sum of positive squares in 2 ways, for example, as 554508304 + 447491716 = 23548^2 + 21154^2 .

It is a Harshad number since it is a multiple of its sum of digits (5).

It is a junction number, because it is equal to n+sod(n) for n = 1001999968 and 1002000013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1002000029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 510245 + ... + 512204.

It is an arithmetic number, because the mean of its divisors is an integer number (67992925).

Almost surely, 2^1002000020 is an apocalyptic number.

1002000020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1002000020 is an abundant number, since it is smaller than the sum of its proper divisors (1445745280).

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

1002000020 is a wasteful number, since it uses less digits than its factorization.

1002000020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1022472 (or 1022463 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 5.

The square root of 1002000020 is about 31654.3838986008. The cubic root of 1002000020 is about 1000.6662293732. Note that the first 3 decimals are identical.

Adding to 1002000020 its reverse (200002001), we get a palindrome (1202002021).

The spelling of 1002000020 in words is "one billion, two million, twenty", and thus it is an aban number and an uban number.