1661285 has 8 divisors (see below), whose sum is σ = 2031480. Its totient is φ = 1303744.

The previous prime is 1661281. The next prime is 1661293. The reversal of 1661285 is 5821661.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 187489 + 1473796 = 433^2 + 1214^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1661285 - 2² = 1661281 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2870 + ... + 3399.

It is an arithmetic number, because the mean of its divisors is an integer number (253935).

2^1661285 is an apocalyptic number.

It is an amenable number.

1661285 is a deficient number, since it is larger than the sum of its proper divisors (370195).

1661285 is an equidigital number, since it uses as much as digits as its factorization.

1661285 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6327.

The product of its digits is 2880, while the sum is 29.

The square root of 1661285 is about 1288.9084529167. The cubic root of 1661285 is about 118.4353591206.

The spelling of 1661285 in words is "one million, six hundred sixty-one thousand, two hundred eighty-five".