3665609985600 has 2688 divisors, whose sum is σ = 15543805132800. Its totient is φ = 835013836800.

The previous prime is 3665609985563. The next prime is 3665609985601. The reversal of 3665609985600 is 65899065663.

3665609985600 is a `hidden beast` number, since 3 + 6 + 6 + 5 + 60 + 9 + 9 + 8 + 560 + 0 = 666.

It is not an unprimeable number, because it can be changed into a prime (3665609985601) by changing a digit.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 46400126361 + ... + 46400126439.

It is an arithmetic number, because the mean of its divisors is an integer number (5782665600).

Almost surely, 2^{3665609985600} is an apocalyptic number.

3665609985600 is a gapful number since it is divisible by the number (30) 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 3665609985600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7771902566400).

3665609985600 is an abundant number, since it is smaller than the sum of its proper divisors (11878195147200).

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

3665609985600 is a wasteful number, since it uses less digits than its factorization.

3665609985600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258 (or 237 counting only the distinct ones).

The product of its (nonzero) digits is 62985600, while the sum is 63.

The spelling of 3665609985600 in words is "three trillion, six hundred sixty-five billion, six hundred nine million, nine hundred eighty-five thousand, six hundred".