4066561 has 4 divisors (see below), whose sum is σ = 4243392. Its totient is φ = 3889732.

The previous prime is 4066537. The next prime is 4066567. The reversal of 4066561 is 1656604.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4066561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4066567) 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, 88381 + ... + 88426.

It is an arithmetic number, because the mean of its divisors is an integer number (1060848).

Almost surely, 2^4066561 is an apocalyptic number.

It is an amenable number.

4066561 is a deficient number, since it is larger than the sum of its proper divisors (176831).

4066561 is a wasteful number, since it uses less digits than its factorization.

4066561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176830.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 4066561 is about 2016.5715955552. The cubic root of 4066561 is about 159.6157576626.

The spelling of 4066561 in words is "four million, sixty-six thousand, five hundred sixty-one".