660420644660 has 72 divisors (see below), whose sum is σ = 1618017649920. Its totient is φ = 226429820064.

The previous prime is 660420644651. The next prime is 660420644683. The reversal of 660420644660 is 66446024066.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 646220 + ... + 1318499.

It is an arithmetic number, because the mean of its divisors is an integer number (22472467360).

Almost surely, 2^660420644660 is an apocalyptic number.

It is an amenable number.

660420644660 is an abundant number, since it is smaller than the sum of its proper divisors (957597005260).

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

660420644660 is an equidigital number, since it uses as much as digits as its factorization.

660420644660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1964763 (or 1964733 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 44.

The spelling of 660420644660 in words is "six hundred sixty billion, four hundred twenty million, six hundred forty-four thousand, six hundred sixty".