20021011 has 8 divisors (see below), whose sum is σ = 20457360. Its totient is φ = 19589472.

The previous prime is 20020943. The next prime is 20021021. The reversal of 20021011 is 11012002.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20021011 - 2¹⁷ = 19889939 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20020985 and 20021003.

It is not an unprimeable number, because it can be changed into a prime (20021021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7941 + ... + 10153.

It is an arithmetic number, because the mean of its divisors is an integer number (2557170).

Almost surely, 2^20021011 is an apocalyptic number.

20021011 is a deficient number, since it is larger than the sum of its proper divisors (436349).

20021011 is a wasteful number, since it uses less digits than its factorization.

20021011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2405.

The product of its (nonzero) digits is 4, while the sum is 7.

The square root of 20021011 is about 4474.4844395751. The cubic root of 20021011 is about 271.5367827733.

Adding to 20021011 its reverse (11012002), we get a palindrome (31033013).

Subtracting from 20021011 its reverse (11012002), we obtain a palindrome (9009009).

The spelling of 20021011 in words is "twenty million, twenty-one thousand, eleven".