55216920 has 128 divisors (see below), whose sum is σ = 184032000. Its totient is φ = 13140480.

The previous prime is 55216919. The next prime is 55216943. The reversal of 55216920 is 2961255.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 77526 + ... + 78234.

It is an arithmetic number, because the mean of its divisors is an integer number (1437750).

Almost surely, 2^55216920 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 55216920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92016000).

55216920 is an abundant number, since it is smaller than the sum of its proper divisors (128815080).

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

55216920 is a wasteful number, since it uses less digits than its factorization.

55216920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 793 (or 789 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 30.

The square root of 55216920 is about 7430.8088388815. The cubic root of 55216920 is about 380.7945517134.

The spelling of 55216920 in words is "fifty-five million, two hundred sixteen thousand, nine hundred twenty".