8005561 has 4 divisors (see below), whose sum is σ = 8021392. Its totient is φ = 7989732.

The previous prime is 8005559. The next prime is 8005573. The reversal of 8005561 is 1655008.

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 not a de Polignac number, because 8005561 - 2¹ = 8005559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8005511) 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, 7131 + ... + 8176.

It is an arithmetic number, because the mean of its divisors is an integer number (2005348).

Almost surely, 2^8005561 is an apocalyptic number.

It is an amenable number.

8005561 is a deficient number, since it is larger than the sum of its proper divisors (15831).

8005561 is a wasteful number, since it uses less digits than its factorization.

8005561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15830.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 8005561 is about 2829.4100091715. The cubic root of 8005561 is about 200.0463309331.

The spelling of 8005561 in words is "eight million, five thousand, five hundred sixty-one".