3506561 has 4 divisors (see below), whose sum is σ = 3514692. Its totient is φ = 3498432.

The previous prime is 3506549. The next prime is 3506567. The reversal of 3506561 is 1656053.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2660161 + 846400 = 1631^2 + 920^2 .

It is a cyclic number.

It is not a de Polignac number, because 3506561 - 2¹⁴ = 3490177 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3506561.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3506567) 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, 3380 + ... + 4293.

It is an arithmetic number, because the mean of its divisors is an integer number (878673).

Almost surely, 2^3506561 is an apocalyptic number.

It is an amenable number.

3506561 is a deficient number, since it is larger than the sum of its proper divisors (8131).

3506561 is an equidigital number, since it uses as much as digits as its factorization.

3506561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8130.

The product of its (nonzero) digits is 2700, while the sum is 26.

The square root of 3506561 is about 1872.5813733988. The cubic root of 3506561 is about 151.9242610896.

The spelling of 3506561 in words is "three million, five hundred six thousand, five hundred sixty-one".