1666241 has 4 divisors (see below), whose sum is σ = 1677012. Its totient is φ = 1655472.

The previous prime is 1666237. The next prime is 1666261. The reversal of 1666241 is 1426661.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1426661 = 79 ⋅18059.

It can be written as a sum of positive squares in 2 ways, for example, as 1256641 + 409600 = 1121^2 + 640^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666241 - 2² = 1666237 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1666241.

It is not an unprimeable number, because it can be changed into a prime (1666201) 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, 5150 + ... + 5463.

It is an arithmetic number, because the mean of its divisors is an integer number (419253).

2^1666241 is an apocalyptic number.

It is an amenable number.

1666241 is a deficient number, since it is larger than the sum of its proper divisors (10771).

1666241 is a wasteful number, since it uses less digits than its factorization.

1666241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10770.

The product of its digits is 1728, while the sum is 26.

The square root of 1666241 is about 1290.8295782170. The cubic root of 1666241 is about 118.5530156175.

The spelling of 1666241 in words is "one million, six hundred sixty-six thousand, two hundred forty-one".