665660257548 has 144 divisors (see below), whose sum is σ = 1835490093696. Its totient is φ = 186125921280.

The previous prime is 665660257547. The next prime is 665660257607. The reversal of 665660257548 is 845752066566.

It is a junction number, because it is equal to n+sod(n) for n = 665660257491 and 665660257500.

It is not an unprimeable number, because it can be changed into a prime (665660257547) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 84610311 + ... + 84618177.

It is an arithmetic number, because the mean of its divisors is an integer number (12746458984).

Almost surely, 2^665660257548 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 665660257548, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (917745046848).

665660257548 is an abundant number, since it is smaller than the sum of its proper divisors (1169829836148).

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

665660257548 is a wasteful number, since it uses less digits than its factorization.

665660257548 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11704 (or 11689 counting only the distinct ones).

The product of its (nonzero) digits is 72576000, while the sum is 60.

The spelling of 665660257548 in words is "six hundred sixty-five billion, six hundred sixty million, two hundred fifty-seven thousand, five hundred forty-eight".