3640665 has 16 divisors (see below), whose sum is σ = 6657408. Its totient is φ = 1664256.

The previous prime is 3640661. The next prime is 3640697. The reversal of 3640665 is 5660463.

It is not a de Polignac number, because 3640665 - 2² = 3640661 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3640661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17232 + ... + 17441.

It is an arithmetic number, because the mean of its divisors is an integer number (416088).

Almost surely, 2^3640665 is an apocalyptic number.

3640665 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

3640665 is a deficient number, since it is larger than the sum of its proper divisors (3016743).

3640665 is a wasteful number, since it uses less digits than its factorization.

3640665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34688.

The product of its (nonzero) digits is 12960, while the sum is 30.

The square root of 3640665 is about 1908.0526722289. The cubic root of 3640665 is about 153.8368007455.

The spelling of 3640665 in words is "three million, six hundred forty thousand, six hundred sixty-five".