18717322428 has 144 divisors (see below), whose sum is σ = 57164889600. Its totient is φ = 5279994720.

The previous prime is 18717322417. The next prime is 18717322453. The reversal of 18717322428 is 82422371781.

18717322428 is a `hidden beast` number, since 187 + 17 + 32 + 2 + 428 = 666.

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 47 ways as a sum of consecutive naturals, for example, 395683 + ... + 440453.

It is an arithmetic number, because the mean of its divisors is an integer number (396978400).

Almost surely, 2^18717322428 is an apocalyptic number.

18717322428 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18717322428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28582444800).

18717322428 is an abundant number, since it is smaller than the sum of its proper divisors (38447567172).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18717322428 is a wasteful number, since it uses less digits than its factorization.

18717322428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44877 (or 44862 counting only the distinct ones).

The product of its digits is 301056, while the sum is 45.

The spelling of 18717322428 in words is "eighteen billion, seven hundred seventeen million, three hundred twenty-two thousand, four hundred twenty-eight".