20021010012 has 72 divisors (see below), whose sum is σ = 51837369584. Its totient is φ = 6511954176.

The previous prime is 20021009999. The next prime is 20021010029. The reversal of 20021010012 is 21001012002.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 20021009976 and 20021010003.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 1686048 + ... + 1697880.

Almost surely, 2^20021010012 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20021010012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25918684792).

20021010012 is an abundant number, since it is smaller than the sum of its proper divisors (31816359572).

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

20021010012 is a wasteful number, since it uses less digits than its factorization.

20021010012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12979 (or 12974 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 20021010012 its reverse (21001012002), we get a palindrome (41022022014).

The spelling of 20021010012 in words is "twenty billion, twenty-one million, ten thousand, twelve".