665225550 has 144 divisors (see below), whose sum is σ = 2034834048. Its totient is φ = 154228800.

The previous prime is 665225503. The next prime is 665225563. The reversal of 665225550 is 55522566.

665225550 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 110929 + ... + 116771.

It is an arithmetic number, because the mean of its divisors is an integer number (14130792).

Almost surely, 2^665225550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665225550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1017417024).

665225550 is an abundant number, since it is smaller than the sum of its proper divisors (1369608498).

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

665225550 is a wasteful number, since it uses less digits than its factorization.

665225550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5895 (or 5887 counting only the distinct ones).

The product of its (nonzero) digits is 90000, while the sum is 36.

The square root of 665225550 is about 25791.9667726213. The cubic root of 665225550 is about 872.9505449404.

The spelling of 665225550 in words is "six hundred sixty-five million, two hundred twenty-five thousand, five hundred fifty".