661105760 has 192 divisors, whose sum is σ = 1921812480. Its totient is φ = 209848320.

The previous prime is 661105747. The next prime is 661105763. The reversal of 661105760 is 67501166.

661105760 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661105763) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 999830 + ... + 1000490.

It is an arithmetic number, because the mean of its divisors is an integer number (10009440).

Almost surely, 2^661105760 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661105760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (960906240).

661105760 is an abundant number, since it is smaller than the sum of its proper divisors (1260706720).

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

661105760 is a wasteful number, since it uses less digits than its factorization.

661105760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 749 (or 741 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 661105760 is about 25711.9769757209. The cubic root of 661105760 is about 871.1447299681.

The spelling of 661105760 in words is "six hundred sixty-one million, one hundred five thousand, seven hundred sixty".