18921897005 has 32 divisors (see below), whose sum is σ = 26434252800. Its totient is φ = 12849822720.

The previous prime is 18921896993. The next prime is 18921897011. The reversal of 18921897005 is 50079812981.

It is not a de Polignac number, because 18921897005 - 2¹⁰ = 18921895981 is a prime.

It is a congruent 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 31 ways as a sum of consecutive naturals, for example, 39071 + ... + 198419.

It is an arithmetic number, because the mean of its divisors is an integer number (826070400).

Almost surely, 2^18921897005 is an apocalyptic number.

It is an amenable number.

18921897005 is a deficient number, since it is larger than the sum of its proper divisors (7512355795).

18921897005 is a wasteful number, since it uses less digits than its factorization.

18921897005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159509.

The product of its (nonzero) digits is 362880, while the sum is 50.

The spelling of 18921897005 in words is "eighteen billion, nine hundred twenty-one million, eight hundred ninety-seven thousand, five".