20211021111 has 8 divisors (see below), whose sum is σ = 26984496640. Its totient is φ = 13455779832.

The previous prime is 20211021101. The next prime is 20211021139. The reversal of 20211021111 is 11112011202.

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

It is not a de Polignac number, because 20211021111 - 2¹⁰ = 20211020087 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211021101) 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, 4555975 + ... + 4560408.

It is an arithmetic number, because the mean of its divisors is an integer number (3373062080).

Almost surely, 2^20211021111 is an apocalyptic number.

20211021111 is a deficient number, since it is larger than the sum of its proper divisors (6773475529).

20211021111 is an equidigital number, since it uses as much as digits as its factorization.

20211021111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9117125.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 20211021111 its reverse (11112011202), we get a palindrome (31323032313).

Subtracting from 20211021111 its reverse (11112011202), we obtain a palindrome (9099009909).

The spelling of 20211021111 in words is "twenty billion, two hundred eleven million, twenty-one thousand, one hundred eleven".