55121760 has 144 divisors (see below), whose sum is σ = 190466640. Its totient is φ = 14515200.

The previous prime is 55121747. The next prime is 55121767. The reversal of 55121760 is 6712155.

It is a tau number, because it is divible by the number of its divisors (144).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55121767) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 145251 + ... + 145629.

It is an arithmetic number, because the mean of its divisors is an integer number (1322685).

Almost surely, 2^55121760 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 55121760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95233320).

55121760 is an abundant number, since it is smaller than the sum of its proper divisors (135344880).

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

55121760 is a wasteful number, since it uses less digits than its factorization.

55121760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501 (or 490 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 27.

The square root of 55121760 is about 7424.4030063029. The cubic root of 55121760 is about 380.5756740824.

The spelling of 55121760 in words is "fifty-five million, one hundred twenty-one thousand, seven hundred sixty".