1566161 has 4 divisors (see below), whose sum is σ = 1570212. Its totient is φ = 1562112.

The previous prime is 1566143. The next prime is 1566163. The reversal of 1566161 is 1616651.

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 65536 + 1500625 = 256^2 + 1225^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1566161 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1566161.

It is not an unprimeable number, because it can be changed into a prime (1566163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1376 + ... + 2241.

It is an arithmetic number, because the mean of its divisors is an integer number (392553).

2^1566161 is an apocalyptic number.

It is an amenable number.

1566161 is a deficient number, since it is larger than the sum of its proper divisors (4051).

1566161 is an equidigital number, since it uses as much as digits as its factorization.

1566161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4050.

The product of its digits is 1080, while the sum is 26.

The square root of 1566161 is about 1251.4635432165. The cubic root of 1566161 is about 116.1302787194.

The spelling of 1566161 in words is "one million, five hundred sixty-six thousand, one hundred sixty-one".