1865556 has 72 divisors (see below), whose sum is σ = 5888064. Its totient is φ = 483840.

The previous prime is 1865551. The next prime is 1865561. The reversal of 1865556 is 6555681.

It is an interprime number because it is at equal distance from previous prime (1865551) and next prime (1865561).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 1865556.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1865551) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2436 + ... + 3108.

2^1865556 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 1865556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2944032).

1865556 is an abundant number, since it is smaller than the sum of its proper divisors (4022508).

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

1865556 is a wasteful number, since it uses less digits than its factorization.

1865556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 701 (or 696 counting only the distinct ones).

The product of its digits is 36000, while the sum is 36.

The square root of 1865556 is about 1365.8535792683. The cubic root of 1865556 is about 123.1032248676.

The spelling of 1865556 in words is "one million, eight hundred sixty-five thousand, five hundred fifty-six".