665606250 has 72 divisors (see below), whose sum is σ = 1802720556. Its totient is φ = 177480000.

The previous prime is 665606237. The next prime is 665606251. The reversal of 665606250 is 52606566.

665606250 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 6 ways, for example, as 4447881 + 661158369 = 2109^2 + 25713^2 .

It is not an unprimeable number, because it can be changed into a prime (665606251) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 50334 + ... + 62166.

Almost surely, 2^665606250 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665606250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (901360278).

665606250 is an abundant number, since it is smaller than the sum of its proper divisors (1137114306).

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

665606250 is a wasteful number, since it uses less digits than its factorization.

665606250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11866 (or 11843 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The square root of 665606250 is about 25799.3459219415. The cubic root of 665606250 is about 873.1170392951.

It can be divided in two parts, 665606 and 250, that added together give a square (665856 = 816²).

The spelling of 665606250 in words is "six hundred sixty-five million, six hundred six thousand, two hundred fifty".