21124642111 has 8 divisors (see below), whose sum is σ = 22261665920. Its totient is φ = 19990138392.

The previous prime is 21124642087. The next prime is 21124642117. The reversal of 21124642111 is 11124642112.

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 21124642111 - 2²¹ = 21122544959 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 (21124642117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 612795 + ... + 646348.

It is an arithmetic number, because the mean of its divisors is an integer number (2782708240).

Almost surely, 2^21124642111 is an apocalyptic number.

21124642111 is a deficient number, since it is larger than the sum of its proper divisors (1137023809).

21124642111 is a wasteful number, since it uses less digits than its factorization.

21124642111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1260045.

The product of its digits is 768, while the sum is 25.

Subtracting from 21124642111 its reverse (11124642112), we obtain a palindrome (9999999999).

The spelling of 21124642111 in words is "twenty-one billion, one hundred twenty-four million, six hundred forty-two thousand, one hundred eleven".