55120520 has 128 divisors (see below), whose sum is σ = 160876800. Its totient is φ = 16505856.

The previous prime is 55120469. The next prime is 55120531. The reversal of 55120520 is 2502155.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 55120492 and 55120501.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 68762 + ... + 69558.

It is an arithmetic number, because the mean of its divisors is an integer number (1256850).

Almost surely, 2^55120520 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 55120520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80438400).

55120520 is an abundant number, since it is smaller than the sum of its proper divisors (105756280).

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

55120520 is a wasteful number, since it uses less digits than its factorization.

With its successor (55120521) it forms an eRAP, since the sums of their prime factors are consecutive (847 and 848).

55120520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 847 (or 843 counting only the distinct ones).

The product of its (nonzero) digits is 500, while the sum is 20.

The square root of 55120520 is about 7424.3194974354. The cubic root of 55120520 is about 380.5728202948.

Adding to 55120520 its reverse (2502155), we get a palindrome (57622675).

The spelling of 55120520 in words is "fifty-five million, one hundred twenty thousand, five hundred twenty".