21404120211 has 16 divisors (see below), whose sum is σ = 32384486400. Its totient is φ = 13965808104.

The previous prime is 21404120197. The next prime is 21404120239. The reversal of 21404120211 is 11202140412.

21404120211 is a `hidden beast` number, since 2 + 1 + 40 + 412 + 0 + 211 = 666.

It is not a de Polignac number, because 21404120211 - 2¹⁵ = 21404087443 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21404120251) 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, 8432191 + ... + 8434728.

It is an arithmetic number, because the mean of its divisors is an integer number (2024030400).

Almost surely, 2^21404120211 is an apocalyptic number.

21404120211 is a deficient number, since it is larger than the sum of its proper divisors (10980366189).

21404120211 is a wasteful number, since it uses less digits than its factorization.

21404120211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16866975 (or 16866969 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21404120211 its reverse (11202140412), we get a palindrome (32606260623).

The spelling of 21404120211 in words is "twenty-one billion, four hundred four million, one hundred twenty thousand, two hundred eleven".