1855805556 has 72 divisors (see below), whose sum is σ = 4768388352. Its totient is φ = 561334400.

The previous prime is 1855805533. The next prime is 1855805569. The reversal of 1855805556 is 6555085581.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1252336 + ... + 1253816.

It is an arithmetic number, because the mean of its divisors is an integer number (66227616).

Almost surely, 2^1855805556 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 1855805556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2384194176).

1855805556 is an abundant number, since it is smaller than the sum of its proper divisors (2912582796).

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

1855805556 is a wasteful number, since it uses less digits than its factorization.

1855805556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2373 (or 2360 counting only the distinct ones).

The product of its (nonzero) digits is 1200000, while the sum is 48.

The square root of 1855805556 is about 43079.0616889458. The cubic root of 1855805556 is about 1228.8838125706.

The spelling of 1855805556 in words is "one billion, eight hundred fifty-five million, eight hundred five thousand, five hundred fifty-six".