1664188416 has 384 divisors, whose sum is σ = 5725137600. Its totient is φ = 477757440.

The previous prime is 1664188369. The next prime is 1664188423. The reversal of 1664188416 is 6148814661.

It is a tau number, because it is divible by the number of its divisors (384).

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is a zygodrome in base 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 87588855 + ... + 87588873.

Almost surely, 2^1664188416 is an apocalyptic number.

1664188416 is a gapful number since it is divisible by the number (16) 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 1664188416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2862568800).

1664188416 is an abundant number, since it is smaller than the sum of its proper divisors (4060949184).

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

1664188416 is an frugal number, since it uses more digits than its factorization.

1664188416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75 (or 35 counting only the distinct ones).

The product of its digits is 221184, while the sum is 45.

The square root of 1664188416 is about 40794.4655069778. The cubic root of 1664188416 is about 1185.0431517694.

The spelling of 1664188416 in words is "one billion, six hundred sixty-four million, one hundred eighty-eight thousand, four hundred sixteen".