18344781504 has 672 divisors, whose sum is σ = 67307968000. Its totient is φ = 4938071040.

The previous prime is 18344781479. The next prime is 18344781541. The reversal of 18344781504 is 40518744381.

18344781504 is a `hidden beast` number, since 1 + 83 + 447 + 81 + 50 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (672).

It is a self number, because there is not a number n which added to its sum of digits gives 18344781504.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 101352294 + ... + 101352474.

Almost surely, 2^18344781504 is an apocalyptic number.

18344781504 is a gapful number since it is divisible by the number (14) 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 18344781504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33653984000).

18344781504 is an abundant number, since it is smaller than the sum of its proper divisors (48963186496).

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

18344781504 is an equidigital number, since it uses as much as digits as its factorization.

18344781504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248 (or 212 counting only the distinct ones).

The product of its (nonzero) digits is 430080, while the sum is 45.

The spelling of 18344781504 in words is "eighteen billion, three hundred forty-four million, seven hundred eighty-one thousand, five hundred four".