18999381600 has 288 divisors, whose sum is σ = 70574545440. Its totient is φ = 4929361920.

The previous prime is 18999381559. The next prime is 18999381617. The reversal of 18999381600 is 618399981.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 787314 + ... + 811086.

It is an arithmetic number, because the mean of its divisors is an integer number (245050505).

Almost surely, 2^18999381600 is an apocalyptic number.

18999381600 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 18999381600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35287272720).

18999381600 is an abundant number, since it is smaller than the sum of its proper divisors (51575163840).

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

18999381600 is a wasteful number, since it uses less digits than its factorization.

18999381600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23839 (or 23820 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 54.

It can be divided in two parts, 18999381 and 600, that added together give a palindrome (18999981).

The spelling of 18999381600 in words is "eighteen billion, nine hundred ninety-nine million, three hundred eighty-one thousand, six hundred".