661505570 has 32 divisors (see below), whose sum is σ = 1305728640. Its totient is φ = 239293440.

The previous prime is 661505569. The next prime is 661505597. The reversal of 661505570 is 75505166.

661505570 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 661505570.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5651 + ... + 36809.

It is an arithmetic number, because the mean of its divisors is an integer number (40804020).

Almost surely, 2^661505570 is an apocalyptic number.

661505570 is a deficient number, since it is larger than the sum of its proper divisors (644223070).

661505570 is a wasteful number, since it uses less digits than its factorization.

661505570 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31370.

The product of its (nonzero) digits is 31500, while the sum is 35.

The square root of 661505570 is about 25719.7505819944. The cubic root of 661505570 is about 871.3203056011.

The spelling of 661505570 in words is "six hundred sixty-one million, five hundred five thousand, five hundred seventy".