55216340 has 72 divisors (see below), whose sum is σ = 126722232. Its totient is φ = 20193280.

The previous prime is 55216333. The next prime is 55216351. The reversal of 55216340 is 4361255.

It can be written as a sum of positive squares in 12 ways, for example, as 18079504 + 37136836 = 4252^2 + 6094^2 .

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 23 ways as a sum of consecutive naturals, for example, 236864 + ... + 237096.

It is an arithmetic number, because the mean of its divisors is an integer number (1760031).

Almost surely, 2^55216340 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 55216340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63361116).

55216340 is an abundant number, since it is smaller than the sum of its proper divisors (71505892).

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

55216340 is a wasteful number, since it uses less digits than its factorization.

55216340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317 (or 298 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 55216340 is about 7430.7698120720. The cubic root of 55216340 is about 380.7932184166.

Adding to 55216340 its reverse (4361255), we get a palindrome (59577595).

The spelling of 55216340 in words is "fifty-five million, two hundred sixteen thousand, three hundred forty".