665645208480 has 960 divisors, whose sum is σ = 2846721411072. Its totient is φ = 143237652480.

The previous prime is 665645208469. The next prime is 665645208509. The reversal of 665645208480 is 84802546566.

665645208480 is a `hidden beast` number, since 66 + 56 + 4 + 52 + 0 + 8 + 480 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 104052642 + ... + 104059038.

Almost surely, 2^665645208480 is an apocalyptic number.

665645208480 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665645208480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1423360705536).

665645208480 is an abundant number, since it is smaller than the sum of its proper divisors (2181076202592).

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

665645208480 is a wasteful number, since it uses less digits than its factorization.

665645208480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6499 (or 6482 counting only the distinct ones).

The product of its (nonzero) digits is 11059200, while the sum is 54.

The spelling of 665645208480 in words is "six hundred sixty-five billion, six hundred forty-five million, two hundred eight thousand, four hundred eighty".