55808820 has 36 divisors (see below), whose sum is σ = 169287300. Its totient is φ = 14882304.

The previous prime is 55808803. The next prime is 55808821. The reversal of 55808820 is 2880855.

55808820 is a `hidden beast` number, since 558 + 0 + 88 + 20 = 666.

55808820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 6780816 + 49028004 = 2604^2 + 7002^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×55808820² = 6229248779584800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55808821) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 154845 + ... + 155204.

It is an arithmetic number, because the mean of its divisors is an integer number (4702425).

Almost surely, 2^55808820 is an apocalyptic number.

It is an amenable number.

55808820 is an abundant number, since it is smaller than the sum of its proper divisors (113478480).

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

55808820 is a wasteful number, since it uses less digits than its factorization.

55808820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310064 (or 310059 counting only the distinct ones).

The product of its (nonzero) digits is 25600, while the sum is 36.

The square root of 55808820 is about 7470.5301016728. The cubic root of 55808820 is about 382.1503661394.

It can be divided in two parts, 5580 and 8820, that added together give a square (14400 = 120²).

The spelling of 55808820 in words is "fifty-five million, eight hundred eight thousand, eight hundred twenty".