661775568 has 40 divisors (see below), whose sum is σ = 1710717888. Its totient is φ = 220445952.

The previous prime is 661775503. The next prime is 661775579. The reversal of 661775568 is 865577166.

661775568 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 661775568.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 88221 + ... + 95427.

Almost surely, 2^661775568 is an apocalyptic number.

It is an amenable number.

661775568 is an abundant number, since it is smaller than the sum of its proper divisors (1048942320).

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

661775568 is a wasteful number, since it uses less digits than its factorization.

661775568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9131 (or 9125 counting only the distinct ones).

The product of its digits is 2116800, while the sum is 51.

The square root of 661775568 is about 25724.9988921283. The cubic root of 661775568 is about 871.4388345805.

The spelling of 661775568 in words is "six hundred sixty-one million, seven hundred seventy-five thousand, five hundred sixty-eight".