21404420054111 has 2 divisors, whose sum is σ = 21404420054112. Its totient is φ = 21404420054110.

The previous prime is 21404420054099. The next prime is 21404420054117. The reversal of 21404420054111 is 11145002440412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21404420054111 - 2¹⁸ = 21404419791967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21404420054117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10702210027055 + 10702210027056.

It is an arithmetic number, because the mean of its divisors is an integer number (10702210027056).

Almost surely, 2^{21404420054111} is an apocalyptic number.

21404420054111 is a deficient number, since it is larger than the sum of its proper divisors (1).

21404420054111 is an equidigital number, since it uses as much as digits as its factorization.

21404420054111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5120, while the sum is 29.

Adding to 21404420054111 its reverse (11145002440412), we get a palindrome (32549422494523).

The spelling of 21404420054111 in words is "twenty-one trillion, four hundred four billion, four hundred twenty million, fifty-four thousand, one hundred eleven".