21404123411 has 16 divisors (see below), whose sum is σ = 24752314368. Its totient is φ = 18292329600.

The previous prime is 21404123381. The next prime is 21404123437. The reversal of 21404123411 is 11432140412.

It is a cyclic number.

It is not a de Polignac number, because 21404123411 - 2²⁶ = 21337014547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21404123471) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95066 + ... + 227696.

It is an arithmetic number, because the mean of its divisors is an integer number (1547019648).

Almost surely, 2^21404123411 is an apocalyptic number.

21404123411 is a deficient number, since it is larger than the sum of its proper divisors (3348190957).

21404123411 is a wasteful number, since it uses less digits than its factorization.

21404123411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133522.

The product of its (nonzero) digits is 768, while the sum is 23.

Adding to 21404123411 its reverse (11432140412), we get a palindrome (32836263823).

The spelling of 21404123411 in words is "twenty-one billion, four hundred four million, one hundred twenty-three thousand, four hundred eleven".