660565650 has 48 divisors (see below), whose sum is σ = 1648314144. Its totient is φ = 175063680.

The previous prime is 660565627. The next prime is 660565691. The reversal of 660565650 is 56565066.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 660565599 and 660565608.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10942 + ... + 37958.

It is an arithmetic number, because the mean of its divisors is an integer number (34339878).

Almost surely, 2^660565650 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 660565650, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (824157072).

660565650 is an abundant number, since it is smaller than the sum of its proper divisors (987748494).

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

660565650 is a wasteful number, since it uses less digits than its factorization.

660565650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27195 (or 27190 counting only the distinct ones).

The product of its (nonzero) digits is 162000, while the sum is 39.

The square root of 660565650 is about 25701.4717477424. The cubic root of 660565650 is about 870.9074294733.

The spelling of 660565650 in words is "six hundred sixty million, five hundred sixty-five thousand, six hundred fifty".