20021011011 has 12 divisors (see below), whose sum is σ = 28938147160. Its totient is φ = 13338613440.

The previous prime is 20021011007. The next prime is 20021011019. The reversal of 20021011011 is 11011012002.

It is a happy number.

It is not a de Polignac number, because 20021011011 - 2² = 20021011007 is a prime.

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

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20021010984 and 20021011002.

It is not an unprimeable number, because it can be changed into a prime (20021011019) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 712726 + ... + 740283.

Almost surely, 2^20021011011 is an apocalyptic number.

20021011011 is a deficient number, since it is larger than the sum of its proper divisors (8917136149).

20021011011 is a wasteful number, since it uses less digits than its factorization.

20021011011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1454546 (or 1454543 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 20021011011 its reverse (11011012002), we get a palindrome (31032023013).

Subtracting from 20021011011 its reverse (11011012002), we obtain a palindrome (9009999009).

The spelling of 20021011011 in words is "twenty billion, twenty-one million, eleven thousand, eleven".