3665801664 has 224 divisors, whose sum is σ = 13041538560. Its totient is φ = 985706496.

The previous prime is 3665801641. The next prime is 3665801669. The reversal of 3665801664 is 4661085663.

3665801664 is a `hidden beast` number, since 3 + 6 + 6 + 580 + 1 + 6 + 64 = 666.

It is a tau number, because it is divible by the number of its divisors (224).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3665801669) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 196719 + ... + 214545.

Almost surely, 2^3665801664 is an apocalyptic number.

3665801664 is a gapful number since it is divisible by the number (34) 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 3665801664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6520769280).

3665801664 is an abundant number, since it is smaller than the sum of its proper divisors (9375736896).

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

3665801664 is a wasteful number, since it uses less digits than its factorization.

3665801664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17872 (or 17856 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The square root of 3665801664 is about 60545.8641362067. The cubic root of 3665801664 is about 1541.9004008403.

The spelling of 3665801664 in words is "three billion, six hundred sixty-five million, eight hundred one thousand, six hundred sixty-four".