18897172105 has 8 divisors (see below), whose sum is σ = 25916121792. Its totient is φ = 12958060848.

The previous prime is 18897172093. The next prime is 18897172123. The reversal of 18897172105 is 50127179881.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18897172105 - 2¹⁵ = 18897139337 is a prime.

It is a super-2 number, since 2×18897172105² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 269959567 + ... + 269959636.

It is an arithmetic number, because the mean of its divisors is an integer number (3239515224).

Almost surely, 2^18897172105 is an apocalyptic number.

It is an amenable number.

18897172105 is a deficient number, since it is larger than the sum of its proper divisors (7018949687).

18897172105 is an equidigital number, since it uses as much as digits as its factorization.

18897172105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 539919215.

The product of its (nonzero) digits is 282240, while the sum is 49.

The spelling of 18897172105 in words is "eighteen billion, eight hundred ninety-seven million, one hundred seventy-two thousand, one hundred five".