18855554715447 has 16 divisors (see below), whose sum is σ = 25323461399040. Its totient is φ = 12479022158400.

The previous prime is 18855554715383. The next prime is 18855554715509. The reversal of 18855554715447 is 74451745555881.

It is not a de Polignac number, because 18855554715447 - 2⁶ = 18855554715383 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18855554715047) 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, 4073922 + ... + 7369392.

It is an arithmetic number, because the mean of its divisors is an integer number (1582716337440).

Almost surely, 2^{18855554715447} is an apocalyptic number.

18855554715447 is a deficient number, since it is larger than the sum of its proper divisors (6467906683593).

18855554715447 is a wasteful number, since it uses less digits than its factorization.

18855554715447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3309334.

The product of its digits is 627200000, while the sum is 69.

The spelling of 18855554715447 in words is "eighteen trillion, eight hundred fifty-five billion, five hundred fifty-four million, seven hundred fifteen thousand, four hundred forty-seven".