665020506600 has 72 divisors (see below), whose sum is σ = 2233360540710. Its totient is φ = 177338801280.

The previous prime is 665020506599. The next prime is 665020506613. The reversal of 665020506600 is 6605020566.

It can be written as a sum of positive squares in 3 ways, for example, as 597340402884 + 67680103716 = 772878^2 + 260154^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 184726119 + ... + 184729718.

Almost surely, 2^665020506600 is an apocalyptic number.

665020506600 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

665020506600 is an abundant number, since it is smaller than the sum of its proper divisors (1568340034110).

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

665020506600 is a wasteful number, since it uses less digits than its factorization.

665020506600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 369455859 (or 369455847 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The spelling of 665020506600 in words is "six hundred sixty-five billion, twenty million, five hundred six thousand, six hundred".