21124021411 has 4 divisors (see below), whose sum is σ = 21125006032. Its totient is φ = 21123036792.

The previous prime is 21124021397. The next prime is 21124021417. The reversal of 21124021411 is 11412042112.

It is a happy number.

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 21124021411 - 2¹¹ = 21124019363 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21124021417) 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, 459396 + ... + 503281.

It is an arithmetic number, because the mean of its divisors is an integer number (5281251508).

Almost surely, 2^21124021411 is an apocalyptic number.

21124021411 is a deficient number, since it is larger than the sum of its proper divisors (984621).

21124021411 is an equidigital number, since it uses as much as digits as its factorization.

21124021411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 984620.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21124021411 its reverse (11412042112), we get a palindrome (32536063523).

The spelling of 21124021411 in words is "twenty-one billion, one hundred twenty-four million, twenty-one thousand, four hundred eleven".