3666501665 has 4 divisors (see below), whose sum is σ = 4399802004. Its totient is φ = 2933201328.

The previous prime is 3666501659. The next prime is 3666501679. The reversal of 3666501665 is 5661056663.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5661056663 = 131 ⋅43214173.

It can be written as a sum of positive squares in 2 ways, for example, as 2133700864 + 1532800801 = 46192^2 + 39151^2 .

It is a cyclic number.

It is not a de Polignac number, because 3666501665 - 2¹⁰ = 3666500641 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 366650162 + ... + 366650171.

It is an arithmetic number, because the mean of its divisors is an integer number (1099950501).

Almost surely, 2^3666501665 is an apocalyptic number.

It is an amenable number.

3666501665 is a deficient number, since it is larger than the sum of its proper divisors (733300339).

3666501665 is an equidigital number, since it uses as much as digits as its factorization.

3666501665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 733300338.

The product of its (nonzero) digits is 583200, while the sum is 44.

The square root of 3666501665 is about 60551.6446102003. The cubic root of 3666501665 is about 1541.9985388219.

The spelling of 3666501665 in words is "three billion, six hundred sixty-six million, five hundred one thousand, six hundred sixty-five".