18994187520 has 1728 divisors, whose sum is σ = 91832832000. Its totient is φ = 3576545280.

The previous prime is 18994187489. The next prime is 18994187521. The reversal of 18994187520 is 2578149981.

It is a happy number.

18994187520 is a `hidden beast` number, since 18 + 9 + 94 + 18 + 7 + 520 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18994187521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 825834229 + ... + 825834251.

It is an arithmetic number, because the mean of its divisors is an integer number (53144000).

Almost surely, 2^18994187520 is an apocalyptic number.

18994187520 is a gapful number since it is divisible by the number (10) 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 18994187520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45916416000).

18994187520 is an abundant number, since it is smaller than the sum of its proper divisors (72838644480).

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

18994187520 is a wasteful number, since it uses less digits than its factorization.

18994187520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101 (or 70 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 54.

The spelling of 18994187520 in words is "eighteen billion, nine hundred ninety-four million, one hundred eighty-seven thousand, five hundred twenty".