556581816 has 96 divisors (see below), whose sum is σ = 1729859040. Its totient is φ = 158367744.

The previous prime is 556581791. The next prime is 556581841. The reversal of 556581816 is 618185655.

556581816 is a `hidden beast` number, since 5 + 56 + 581 + 8 + 16 = 666.

It is an interprime number because it is at equal distance from previous prime (556581791) and next prime (556581841).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 127380 + ... + 131676.

It is an arithmetic number, because the mean of its divisors is an integer number (18019365).

Almost surely, 2^556581816 is an apocalyptic number.

556581816 is a gapful number since it is divisible by the number (56) 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 556581816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (864929520).

556581816 is an abundant number, since it is smaller than the sum of its proper divisors (1173277224).

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

556581816 is a wasteful number, since it uses less digits than its factorization.

556581816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4573 (or 4566 counting only the distinct ones).

The product of its digits is 288000, while the sum is 45.

The square root of 556581816 is about 23591.9862665270. The cubic root of 556581816 is about 822.5765752500.

The spelling of 556581816 in words is "five hundred fifty-six million, five hundred eighty-one thousand, eight hundred sixteen".