18784121811 has 16 divisors (see below), whose sum is σ = 30825225984. Its totient is φ = 9908108064.

The previous prime is 18784121789. The next prime is 18784121891. The reversal of 18784121811 is 11812148781.

It is not a de Polignac number, because 18784121811 - 2¹⁷ = 18783990739 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18784121891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34402881 + ... + 34403426.

It is an arithmetic number, because the mean of its divisors is an integer number (1926576624).

Almost surely, 2^18784121811 is an apocalyptic number.

18784121811 is a deficient number, since it is larger than the sum of its proper divisors (12041104173).

18784121811 is a wasteful number, since it uses less digits than its factorization.

18784121811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68806330.

The product of its digits is 28672, while the sum is 42.

The spelling of 18784121811 in words is "eighteen billion, seven hundred eighty-four million, one hundred twenty-one thousand, eight hundred eleven".