1806556 has 24 divisors (see below), whose sum is σ = 3459456.
Its totient is φ = 821760.
The previous prime is 1806551. The next prime is 1806557. The reversal of 1806556 is 6556081.
It is a super-2 number, since 2×18065562 = 6527289162272, which contains 22 as substring.
It is a Harshad number since it is a multiple of its sum of digits (31).
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (1806551) 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, 1680 + ... + 2536.
It is an arithmetic number, because the mean of its divisors is an integer number (144144).
21806556 is an apocalyptic number.
It is an amenable number.
1806556 is a deficient number, since it is larger than the sum of its proper divisors (1652900).
1806556 is a wasteful number, since it uses less digits than its factorization.
1806556 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 909 (or 907 counting only the distinct ones).
The product of its (nonzero) digits is 7200, while the sum is 31.
The square root of 1806556 is about 1344.0818427462.
The cubic root of 1806556 is about 121.7915458481.
The spelling of 1806556 in words is "one million, eight hundred six thousand, five hundred fifty-six".