20211111121 has 4 divisors (see below), whose sum is σ = 20365394544. Its totient is φ = 20056827700.

The previous prime is 20211111073. The next prime is 20211111203. The reversal of 20211111121 is 12111111202.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20211111121 - 2²³ = 20202722513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20211121121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77141515 + ... + 77141776.

It is an arithmetic number, because the mean of its divisors is an integer number (5091348636).

Almost surely, 2^20211111121 is an apocalyptic number.

It is an amenable number.

20211111121 is a deficient number, since it is larger than the sum of its proper divisors (154283423).

20211111121 is a wasteful number, since it uses less digits than its factorization.

20211111121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154283422.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 20211111121 its reverse (12111111202), we get a palindrome (32322222323).

The spelling of 20211111121 in words is "twenty billion, two hundred eleven million, one hundred eleven thousand, one hundred twenty-one".