18440536608 has 144 divisors (see below), whose sum is σ = 57023628480. Its totient is φ = 5618806272.

The previous prime is 18440536601. The next prime is 18440536637. The reversal of 18440536608 is 80663504481.

18440536608 is a `hidden beast` number, since 1 + 8 + 4 + 4 + 0 + 5 + 36 + 608 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is not an unprimeable number, because it can be changed into a prime (18440536601) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 361723 + ... + 409541.

It is an arithmetic number, because the mean of its divisors is an integer number (395997420).

Almost surely, 2^18440536608 is an apocalyptic number.

18440536608 is a gapful number since it is divisible by the number (18) 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 18440536608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28511814240).

18440536608 is an abundant number, since it is smaller than the sum of its proper divisors (38583091872).

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

18440536608 is a wasteful number, since it uses less digits than its factorization.

18440536608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47951 (or 47940 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 45.

The spelling of 18440536608 in words is "eighteen billion, four hundred forty million, five hundred thirty-six thousand, six hundred eight".