55218072 has 128 divisors (see below), whose sum is σ = 172085760. Its totient is φ = 14376960.

The previous prime is 55218071. The next prime is 55218073. The reversal of 55218072 is 27081255.

55218072 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (55218071) and next prime (55218073).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55218071) 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 31 ways as a sum of consecutive naturals, for example, 286008 + ... + 286200.

It is an arithmetic number, because the mean of its divisors is an integer number (1344420).

Almost surely, 2^55218072 is an apocalyptic number.

55218072 is a gapful number since it is divisible by the number (52) 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 55218072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86042880).

55218072 is an abundant number, since it is smaller than the sum of its proper divisors (116867688).

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

55218072 is a wasteful number, since it uses less digits than its factorization.

55218072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 353 (or 349 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 30.

The square root of 55218072 is about 7430.8863535920. The cubic root of 55218072 is about 380.7971998888.

The spelling of 55218072 in words is "fifty-five million, two hundred eighteen thousand, seventy-two".