1661436 has 72 divisors (see below), whose sum is σ = 5066880. Its totient is φ = 448416.

The previous prime is 1661431. The next prime is 1661437. The reversal of 1661436 is 6341661.

1661436 is a `hidden beast` number, since 16 + 614 + 36 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a zygodrome in base 6.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661431) 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 23 ways as a sum of consecutive naturals, for example, 4615 + ... + 4961.

2^1661436 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1661436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2533440).

1661436 is an abundant number, since it is smaller than the sum of its proper divisors (3405444).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1661436 is a wasteful number, since it uses less digits than its factorization.

1661436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383 (or 378 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 1661436 is about 1288.9670282827. The cubic root of 1661436 is about 118.4389473465.

The spelling of 1661436 in words is "one million, six hundred sixty-one thousand, four hundred thirty-six".