55381240 has 64 divisors (see below), whose sum is σ = 137712960. Its totient is φ = 19937280.

The previous prime is 55381211. The next prime is 55381241. The reversal of 55381240 is 4218355.

55381240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 55381199 and 55381208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55381241) 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, 13870 + ... + 17410.

It is an arithmetic number, because the mean of its divisors is an integer number (2151765).

Almost surely, 2^55381240 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 55381240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68856480).

55381240 is an abundant number, since it is smaller than the sum of its proper divisors (82331720).

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

55381240 is a wasteful number, since it uses less digits than its factorization.

55381240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3592 (or 3588 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 55381240 is about 7441.8572950575. The cubic root of 55381240 is about 381.1719130588.

Adding to 55381240 its reverse (4218355), we get a palindrome (59599595).

The spelling of 55381240 in words is "fifty-five million, three hundred eighty-one thousand, two hundred forty".