21175378105 has 16 divisors (see below), whose sum is σ = 29190996864. Its totient is φ = 14445020160.

The previous prime is 21175378097. The next prime is 21175378123. The reversal of 21175378105 is 50187357112.

It is not a de Polignac number, because 21175378105 - 2³ = 21175378097 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1560631 + ... + 1574140.

It is an arithmetic number, because the mean of its divisors is an integer number (1824437304).

Almost surely, 2^21175378105 is an apocalyptic number.

It is an amenable number.

21175378105 is a deficient number, since it is larger than the sum of its proper divisors (8015618759).

21175378105 is a wasteful number, since it uses less digits than its factorization.

21175378105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3134976.

The product of its (nonzero) digits is 58800, while the sum is 40.

The spelling of 21175378105 in words is "twenty-one billion, one hundred seventy-five million, three hundred seventy-eight thousand, one hundred five".