18690444368 has 80 divisors (see below), whose sum is σ = 40073792256. Its totient is φ = 8399677440.

The previous prime is 18690444361. The next prime is 18690444413. The reversal of 18690444368 is 86344409681.

It is a Cunningham number, because it is equal to 136713²-1.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18690444361) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4646198 + ... + 4650218.

Almost surely, 2^18690444368 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 18690444368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20036896128).

18690444368 is an abundant number, since it is smaller than the sum of its proper divisors (21383347888).

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

18690444368 is a wasteful number, since it uses less digits than its factorization.

18690444368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4812 (or 4806 counting only the distinct ones).

The product of its (nonzero) digits is 3981312, while the sum is 53.

The spelling of 18690444368 in words is "eighteen billion, six hundred ninety million, four hundred forty-four thousand, three hundred sixty-eight".