665839538496 has 280 divisors, whose sum is σ = 2246810791104. Its totient is φ = 192996587520.

The previous prime is 665839538449. The next prime is 665839538501. The reversal of 665839538496 is 694835938566.

665839538496 is a `hidden beast` number, since 6 + 6 + 5 + 83 + 9 + 53 + 8 + 496 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1057716 + ... + 1565388.

Almost surely, 2^665839538496 is an apocalyptic number.

665839538496 is a gapful number since it is divisible by the number (66) 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 665839538496, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1123405395552).

665839538496 is an abundant number, since it is smaller than the sum of its proper divisors (1580971252608).

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

665839538496 is a wasteful number, since it uses less digits than its factorization.

665839538496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 507731 (or 507712 counting only the distinct ones).

The product of its digits is 1007769600, while the sum is 72.

The spelling of 665839538496 in words is "six hundred sixty-five billion, eight hundred thirty-nine million, five hundred thirty-eight thousand, four hundred ninety-six".