665366243520 has 224 divisors, whose sum is σ = 2311561357056. Its totient is φ = 160812748800.

The previous prime is 665366243497. The next prime is 665366243543. The reversal of 665366243520 is 25342663566.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (665366243497) and next prime (665366243543).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 665366243520.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3400182 + ... + 3590538.

It is an arithmetic number, because the mean of its divisors is an integer number (10319470344).

Almost surely, 2^665366243520 is an apocalyptic number.

665366243520 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 665366243520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1155780678528).

665366243520 is an abundant number, since it is smaller than the sum of its proper divisors (1646195113536).

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

665366243520 is a wasteful number, since it uses less digits than its factorization.

665366243520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190719 (or 190709 counting only the distinct ones).

The product of its (nonzero) digits is 4665600, while the sum is 48.

The spelling of 665366243520 in words is "six hundred sixty-five billion, three hundred sixty-six million, two hundred forty-three thousand, five hundred twenty".