4391561 has 4 divisors (see below), whose sum is σ = 4399824. Its totient is φ = 4383300.

The previous prime is 4391549. The next prime is 4391579. The reversal of 4391561 is 1651934.

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 4391561 - 2¹⁴ = 4375177 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (4391521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3275 + ... + 4416.

It is an arithmetic number, because the mean of its divisors is an integer number (1099956).

Almost surely, 2^4391561 is an apocalyptic number.

It is an amenable number.

4391561 is a deficient number, since it is larger than the sum of its proper divisors (8263).

4391561 is an equidigital number, since it uses as much as digits as its factorization.

4391561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8262.

The product of its digits is 3240, while the sum is 29.

The square root of 4391561 is about 2095.6051631927. The cubic root of 4391561 is about 163.7594256758.

The spelling of 4391561 in words is "four million, three hundred ninety-one thousand, five hundred sixty-one".