21405222042105 has 192 divisors, whose sum is σ = 41155411046400. Its totient is φ = 9459729100800.

The previous prime is 21405222042101. The next prime is 21405222042179. The reversal of 21405222042105 is 50124022250412.

It is not a de Polignac number, because 21405222042105 - 2² = 21405222042101 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21405222042101) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 95514985 + ... + 95738825.

It is an arithmetic number, because the mean of its divisors is an integer number (214351099200).

Almost surely, 2^{21405222042105} is an apocalyptic number.

It is an amenable number.

21405222042105 is a deficient number, since it is larger than the sum of its proper divisors (19750189004295).

21405222042105 is a wasteful number, since it uses less digits than its factorization.

21405222042105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223996 (or 223985 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 30.

Adding to 21405222042105 its reverse (50124022250412), we get a palindrome (71529244292517).

The spelling of 21405222042105 in words is "twenty-one trillion, four hundred five billion, two hundred twenty-two million, forty-two thousand, one hundred five".