55318428 has 72 divisors (see below), whose sum is σ = 157837680. Its totient is φ = 16181760.

The previous prime is 55318423. The next prime is 55318433. The reversal of 55318428 is 82481355.

It is a happy number.

55318428 is a `hidden beast` number, since 553 + 1 + 84 + 28 = 666.

55318428 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 (55318423) and next prime (55318433).

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

It is a junction number, because it is equal to n+sod(n) for n = 55318392 and 55318401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55318423) 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 23 ways as a sum of consecutive naturals, for example, 9076 + ... + 13892.

It is an arithmetic number, because the mean of its divisors is an integer number (2192190).

Almost surely, 2^55318428 is an apocalyptic number.

55318428 is a gapful number since it is divisible by the number (58) 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 55318428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78918840).

55318428 is an abundant number, since it is smaller than the sum of its proper divisors (102519252).

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

55318428 is a wasteful number, since it uses less digits than its factorization.

55318428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4867 (or 4862 counting only the distinct ones).

The product of its digits is 38400, while the sum is 36.

The square root of 55318428 is about 7437.6359147245. The cubic root of 55318428 is about 381.0277533671.

It can be divided in two parts, 553 and 18428, that added together give a palindrome (18981).

The spelling of 55318428 in words is "fifty-five million, three hundred eighteen thousand, four hundred twenty-eight".