21404041111 has 4 divisors (see below), whose sum is σ = 21405982752. Its totient is φ = 21402099472.

The previous prime is 21404041093. The next prime is 21404041159. The reversal of 21404041111 is 11114040412.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21404041111 is a prime.

It is a super-2 number, since 2×21404041111² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21404041511) 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, 954190 + ... + 976363.

It is an arithmetic number, because the mean of its divisors is an integer number (5351495688).

Almost surely, 2^21404041111 is an apocalyptic number.

21404041111 is a deficient number, since it is larger than the sum of its proper divisors (1941641).

21404041111 is a wasteful number, since it uses less digits than its factorization.

21404041111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1941640.

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

Adding to 21404041111 its reverse (11114040412), we get a palindrome (32518081523).

The spelling of 21404041111 in words is "twenty-one billion, four hundred four million, forty-one thousand, one hundred eleven".