661536705 has 8 divisors (see below), whose sum is σ = 1058458752. Its totient is φ = 352819568.

The previous prime is 661536697. The next prime is 661536709. The reversal of 661536705 is 507635166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 661536705 - 2³ = 661536697 is a prime.

It is not an unprimeable number, because it can be changed into a prime (661536709) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22051209 + ... + 22051238.

It is an arithmetic number, because the mean of its divisors is an integer number (132307344).

Almost surely, 2^661536705 is an apocalyptic number.

It is an amenable number.

661536705 is a deficient number, since it is larger than the sum of its proper divisors (396922047).

661536705 is a wasteful number, since it uses less digits than its factorization.

661536705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44102455.

The product of its (nonzero) digits is 113400, while the sum is 39.

The square root of 661536705 is about 25720.3558490158. The cubic root of 661536705 is about 871.3339754946. Note that the first 3 decimals are identical.

The spelling of 661536705 in words is "six hundred sixty-one million, five hundred thirty-six thousand, seven hundred five".