1820856 has 16 divisors (see below), whose sum is σ = 4552200. Its totient is φ = 606944.

The previous prime is 1820843. The next prime is 1820857. The reversal of 1820856 is 6580281.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1820857) 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 3 ways as a sum of consecutive naturals, for example, 37911 + ... + 37958.

2^1820856 is an apocalyptic number.

It is an amenable number.

1820856 is an abundant number, since it is smaller than the sum of its proper divisors (2731344).

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

1820856 is a wasteful number, since it uses less digits than its factorization.

1820856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75878 (or 75874 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 30.

The square root of 1820856 is about 1349.3909737359. The cubic root of 1820856 is about 122.1120532814.

The spelling of 1820856 in words is "one million, eight hundred twenty thousand, eight hundred fifty-six".