1855820 has 12 divisors (see below), whose sum is σ = 3897264. Its totient is φ = 742320.

The previous prime is 1855817. The next prime is 1855823. The reversal of 1855820 is 285581.

It is an interprime number because it is at equal distance from previous prime (1855817) and next prime (1855823).

It is not an unprimeable number, because it can be changed into a prime (1855823) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46376 + ... + 46415.

It is an arithmetic number, because the mean of its divisors is an integer number (324772).

2^1855820 is an apocalyptic number.

1855820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1855820 is an abundant number, since it is smaller than the sum of its proper divisors (2041444).

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

1855820 is a wasteful number, since it uses less digits than its factorization.

1855820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92800 (or 92798 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 29.

The square root of 1855820 is about 1362.2848453976. The cubic root of 1855820 is about 122.8887000755. Note that the first 3 decimals are identical.

The spelling of 1855820 in words is "one million, eight hundred fifty-five thousand, eight hundred twenty".