18709821312 has 384 divisors, whose sum is σ = 62720501760. Its totient is φ = 4912330752.

The previous prime is 18709821311. The next prime is 18709821421. The reversal of 18709821312 is 21312890781.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18709821311) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 83900433 + ... + 83900655.

It is an arithmetic number, because the mean of its divisors is an integer number (163334640).

Almost surely, 2^18709821312 is an apocalyptic number.

18709821312 is a gapful number since it is divisible by the number (12) 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 18709821312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31360250880).

18709821312 is an abundant number, since it is smaller than the sum of its proper divisors (44010680448).

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

18709821312 is an frugal number, since it uses more digits than its factorization.

18709821312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288 (or 248 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 42.

The spelling of 18709821312 in words is "eighteen billion, seven hundred nine million, eight hundred twenty-one thousand, three hundred twelve".