21110255250405 has 16 divisors (see below), whose sum is σ = 33798941064000. Its totient is φ = 11251291912448.

The previous prime is 21110255250401. The next prime is 21110255250407. The reversal of 21110255250405 is 50405255201112.

It is a cyclic number.

It is not a de Polignac number, because 21110255250405 - 2² = 21110255250401 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110255250401) 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, 469407252 + ... + 469452221.

It is an arithmetic number, because the mean of its divisors is an integer number (2112433816500).

Almost surely, 2^{21110255250405} is an apocalyptic number.

It is an amenable number.

21110255250405 is a deficient number, since it is larger than the sum of its proper divisors (12688685813595).

21110255250405 is a wasteful number, since it uses less digits than its factorization.

21110255250405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 938860980.

The product of its (nonzero) digits is 20000, while the sum is 33.

The spelling of 21110255250405 in words is "twenty-one trillion, one hundred ten billion, two hundred fifty-five million, two hundred fifty thousand, four hundred five".