665670559500 has 144 divisors (see below), whose sum is σ = 2105990796000. Its totient is φ = 177003100800.

The previous prime is 665670559387. The next prime is 665670559507. The reversal of 665670559500 is 5955076566.

It is a happy number.

665670559500 is a `hidden beast` number, since 6 + 65 + 6 + 70 + 5 + 5 + 9 + 500 = 666.

It is not an unprimeable number, because it can be changed into a prime (665670559507) 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, 1358571 + ... + 1782429.

Almost surely, 2^665670559500 is an apocalyptic number.

665670559500 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 665670559500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1052995398000).

665670559500 is an abundant number, since it is smaller than the sum of its proper divisors (1440320236500).

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

665670559500 is a wasteful number, since it uses less digits than its factorization.

665670559500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 424233 (or 424218 counting only the distinct ones).

The product of its (nonzero) digits is 8505000, while the sum is 54.

The spelling of 665670559500 in words is "six hundred sixty-five billion, six hundred seventy million, five hundred fifty-nine thousand, five hundred".