3566021 has 4 divisors (see below), whose sum is σ = 3570444. Its totient is φ = 3561600.

The previous prime is 3565979. The next prime is 3566027. The reversal of 3566021 is 1206653.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 2515396 + 1050625 = 1586^2 + 1025^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3566021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3566027) 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, 620 + ... + 2741.

It is an arithmetic number, because the mean of its divisors is an integer number (892611).

Almost surely, 2^3566021 is an apocalyptic number.

It is an amenable number.

3566021 is a deficient number, since it is larger than the sum of its proper divisors (4423).

3566021 is a wasteful number, since it uses less digits than its factorization.

3566021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4422.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 3566021 is about 1888.3911141498. The cubic root of 3566021 is about 152.7781682806.

The spelling of 3566021 in words is "three million, five hundred sixty-six thousand, twenty-one".