1661359 has 16 divisors (see below), whose sum is σ = 2101248. Its totient is φ = 1279872.

The previous prime is 1661353. The next prime is 1661431. The reversal of 1661359 is 9531661.

It is a cyclic number.

It is not a de Polignac number, because 1661359 - 2⁵ = 1661327 is a prime.

It is a super-2 number, since 2×1661359² = 5520227453762, which contains 22 as substring.

It is an Ulam number.

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 1661359.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661353) 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 15 ways as a sum of consecutive naturals, for example, 2434 + ... + 3040.

It is an arithmetic number, because the mean of its divisors is an integer number (131328).

2^1661359 is an apocalyptic number.

1661359 is a deficient number, since it is larger than the sum of its proper divisors (439889).

1661359 is a wasteful number, since it uses less digits than its factorization.

1661359 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654.

The product of its digits is 4860, while the sum is 31.

The square root of 1661359 is about 1288.9371590578. The cubic root of 1661359 is about 118.4371176161.

The spelling of 1661359 in words is "one million, six hundred sixty-one thousand, three hundred fifty-nine".