1555808256 has 120 divisors (see below), whose sum is σ = 4610972240. Its totient is φ = 518455296.

The previous prime is 1555808249. The next prime is 1555808257. The reversal of 1555808256 is 6528085551.

1555808256 is a `hidden beast` number, since 15 + 5 + 580 + 8 + 2 + 56 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1555808257) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 440610 + ... + 444126.

Almost surely, 2^1555808256 is an apocalyptic number.

1555808256 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1555808256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2305486120).

1555808256 is an abundant number, since it is smaller than the sum of its proper divisors (3055163984).

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

1555808256 is an frugal number, since it uses more digits than its factorization.

1555808256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3554 (or 3522 counting only the distinct ones).

The product of its (nonzero) digits is 480000, while the sum is 45.

The square root of 1555808256 is about 39443.7353200733. The cubic root of 1555808256 is about 1158.7382872896.

The spelling of 1555808256 in words is "one billion, five hundred fifty-five million, eight hundred eight thousand, two hundred fifty-six".