3656591 has 4 divisors (see below), whose sum is σ = 3741672. Its totient is φ = 3571512.

The previous prime is 3656573. The next prime is 3656593. The reversal of 3656591 is 1956563.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 3656591 - 2¹⁴ = 3640207 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3656593) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42476 + ... + 42561.

It is an arithmetic number, because the mean of its divisors is an integer number (935418).

Almost surely, 2^3656591 is an apocalyptic number.

3656591 is a deficient number, since it is larger than the sum of its proper divisors (85081).

3656591 is an equidigital number, since it uses as much as digits as its factorization.

3656591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85080.

The product of its digits is 24300, while the sum is 35.

The square root of 3656591 is about 1912.2214829878. The cubic root of 3656591 is about 154.0607928870.

The spelling of 3656591 in words is "three million, six hundred fifty-six thousand, five hundred ninety-one".