65557220 has 24 divisors (see below), whose sum is σ = 144916800. Its totient is φ = 24842592.

The previous prime is 65557213. The next prime is 65557223. The reversal of 65557220 is 2275556.

65557220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (65557223) 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 7 ways as a sum of consecutive naturals, for example, 85880 + ... + 86639.

It is an arithmetic number, because the mean of its divisors is an integer number (6038200).

Almost surely, 2^65557220 is an apocalyptic number.

It is an amenable number.

65557220 is an abundant number, since it is smaller than the sum of its proper divisors (79359580).

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

65557220 is a wasteful number, since it uses less digits than its factorization.

65557220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172547 (or 172545 counting only the distinct ones).

The product of its (nonzero) digits is 21000, while the sum is 32.

The square root of 65557220 is about 8096.7413198150. The cubic root of 65557220 is about 403.2182461220.

It can be divided in two parts, 655 and 57220, that added together give a palindrome (57875).

The spelling of 65557220 in words is "sixty-five million, five hundred fifty-seven thousand, two hundred twenty".