661705705600 has 96 divisors (see below), whose sum is σ = 1669399401600. Its totient is φ = 259050685440.

The previous prime is 661705705513. The next prime is 661705705607. The reversal of 661705705600 is 6507507166.

It is not an unprimeable number, because it can be changed into a prime (661705705607) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2049420 + ... + 2350219.

It is an arithmetic number, because the mean of its divisors is an integer number (17389577100).

Almost surely, 2^661705705600 is an apocalyptic number.

It is an amenable number.

661705705600 is an abundant number, since it is smaller than the sum of its proper divisors (1007693696000).

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

661705705600 is a wasteful number, since it uses less digits than its factorization.

661705705600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4399710 (or 4399693 counting only the distinct ones).

The product of its (nonzero) digits is 264600, while the sum is 43.

The spelling of 661705705600 in words is "six hundred sixty-one billion, seven hundred five million, seven hundred five thousand, six hundred".