3655521 has 6 divisors (see below), whose sum is σ = 5280210. Its totient is φ = 2437008.

The previous prime is 3655513. The next prime is 3655541. The reversal of 3655521 is 1255563.

3655521 is a `hidden beast` number, since 3 + 655 + 5 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 3651921 + 3600 = 1911^2 + 60^2 .

It is not a de Polignac number, because 3655521 - 2³ = 3655513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3655501) 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 5 ways as a sum of consecutive naturals, for example, 203076 + ... + 203093.

It is an arithmetic number, because the mean of its divisors is an integer number (880035).

Almost surely, 2^3655521 is an apocalyptic number.

It is an amenable number.

3655521 is a deficient number, since it is larger than the sum of its proper divisors (1624689).

3655521 is a wasteful number, since it uses less digits than its factorization.

3655521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 406175 (or 406172 counting only the distinct ones).

The product of its digits is 4500, while the sum is 27.

The square root of 3655521 is about 1911.9416832111. The cubic root of 3655521 is about 154.0457642141.

It can be divided in two parts, 365 and 5521, that added together give a triangular number (5886 = T₁₀₈).

The spelling of 3655521 in words is "three million, six hundred fifty-five thousand, five hundred twenty-one".