660561700 has 72 divisors (see below), whose sum is σ = 1478030400. Its totient is φ = 256099200.

The previous prime is 660561683. The next prime is 660561709. The reversal of 660561700 is 7165066.

It is not an unprimeable number, because it can be changed into a prime (660561709) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 640185 + ... + 641215.

It is an arithmetic number, because the mean of its divisors is an integer number (20528200).

Almost surely, 2^660561700 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 660561700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (739015200).

660561700 is an abundant number, since it is smaller than the sum of its proper divisors (817468700).

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

660561700 is a wasteful number, since it uses less digits than its factorization.

660561700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1237 (or 1230 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 660561700 is about 25701.3949037791. The cubic root of 660561700 is about 870.9056935413.

The spelling of 660561700 in words is "six hundred sixty million, five hundred sixty-one thousand, seven hundred".