21124022042111 has 4 divisors (see below), whose sum is σ = 21124171182792. Its totient is φ = 21123872901432.

The previous prime is 21124022042089. The next prime is 21124022042197. The reversal of 21124022042111 is 11124022042112.

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 21124022042111 - 2⁴² = 16725975531007 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 (21124022048111) 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, 74357681 + ... + 74641226.

It is an arithmetic number, because the mean of its divisors is an integer number (5281042795698).

Almost surely, 2^{21124022042111} is an apocalyptic number.

21124022042111 is a deficient number, since it is larger than the sum of its proper divisors (149140681).

21124022042111 is a wasteful number, since it uses less digits than its factorization.

21124022042111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149140680.

The product of its (nonzero) digits is 512, while the sum is 23.

Adding to 21124022042111 its reverse (11124022042112), we get a palindrome (32248044084223).

Subtracting from 21124022042111 its reverse (11124022042112), we obtain a palindrome (9999999999999).

The spelling of 21124022042111 in words is "twenty-one trillion, one hundred twenty-four billion, twenty-two million, forty-two thousand, one hundred eleven".