18940387648 has 112 divisors (see below), whose sum is σ = 46411432704. Its totient is φ = 7468093440.

The previous prime is 18940387619. The next prime is 18940387721. The reversal of 18940387648 is 84678304981.

It is a tau number, because it is divible by the number of its divisors (112).

It is a junction number, because it is equal to n+sod(n) for n = 18940387592 and 18940387601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1806036 + ... + 1816492.

It is an arithmetic number, because the mean of its divisors is an integer number (414387792).

Almost surely, 2^18940387648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18940387648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23205716352).

18940387648 is an abundant number, since it is smaller than the sum of its proper divisors (27471045056).

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

18940387648 is a wasteful number, since it uses less digits than its factorization.

18940387648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10800 (or 10790 counting only the distinct ones).

The product of its (nonzero) digits is 9289728, while the sum is 58.

The spelling of 18940387648 in words is "eighteen billion, nine hundred forty million, three hundred eighty-seven thousand, six hundred forty-eight".