55782220 has 48 divisors (see below), whose sum is σ = 127925280. Its totient is φ = 20307456.

The previous prime is 55782193. The next prime is 55782227. The reversal of 55782220 is 2228755.

55782220 is digitally balanced in base 2 and base 9, because in such bases it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×55782220² = 6223312136256800, which contains 22 as substring.

55782220 is strictly pandigital in base 9.

It is not an unprimeable number, because it can be changed into a prime (55782227) 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 15 ways as a sum of consecutive naturals, for example, 17511 + ... + 20449.

It is an arithmetic number, because the mean of its divisors is an integer number (2665110).

Almost surely, 2^55782220 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 55782220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63962640).

55782220 is an abundant number, since it is smaller than the sum of its proper divisors (72143060).

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

55782220 is a wasteful number, since it uses less digits than its factorization.

55782220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3034 (or 3032 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 31.

The square root of 55782220 is about 7468.7495606694. The cubic root of 55782220 is about 382.0896420748.

The spelling of 55782220 in words is "fifty-five million, seven hundred eighty-two thousand, two hundred twenty".