3663561 has 16 divisors (see below), whose sum is σ = 5610240. Its totient is φ = 2103120.

The previous prime is 3663559. The next prime is 3663563. The reversal of 3663561 is 1653663.

It is an interprime number because it is at equal distance from previous prime (3663559) and next prime (3663563).

It is not a de Polignac number, because 3663561 - 2¹ = 3663559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3663563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2295 + ... + 3548.

It is an arithmetic number, because the mean of its divisors is an integer number (350640).

Almost surely, 2^3663561 is an apocalyptic number.

It is an amenable number.

3663561 is a deficient number, since it is larger than the sum of its proper divisors (1946679).

3663561 is a wasteful number, since it uses less digits than its factorization.

3663561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5876.

The product of its digits is 9720, while the sum is 30.

The square root of 3663561 is about 1914.0431029629. The cubic root of 3663561 is about 154.1586182634.

It can be divided in two parts, 3663 and 561, that added together give a palindrome (4224).

The spelling of 3663561 in words is "three million, six hundred sixty-three thousand, five hundred sixty-one".