21132120111 has 4 divisors (see below), whose sum is σ = 28176160152. Its totient is φ = 14088080072.

The previous prime is 21132120103. The next prime is 21132120133. The reversal of 21132120111 is 11102123112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21132120111 - 2³ = 21132120103 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21132120101) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3522020016 + ... + 3522020021.

It is an arithmetic number, because the mean of its divisors is an integer number (7044040038).

Almost surely, 2^21132120111 is an apocalyptic number.

21132120111 is a deficient number, since it is larger than the sum of its proper divisors (7044040041).

21132120111 is an equidigital number, since it uses as much as digits as its factorization.

21132120111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7044040040.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21132120111 its reverse (11102123112), we get a palindrome (32234243223).

The spelling of 21132120111 in words is "twenty-one billion, one hundred thirty-two million, one hundred twenty thousand, one hundred eleven".