1200665165520 has 120 divisors (see below), whose sum is σ = 3733771764384. Its totient is φ = 319170595328.

The previous prime is 1200665165473. The next prime is 1200665165521. The reversal of 1200665165520 is 255615660021.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (120).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1200665165521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 316212262 + ... + 316216058.

Almost surely, 2^{1200665165520} is an apocalyptic number.

1200665165520 is a gapful number since it is divisible by the number (10) 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 1200665165520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1866885882192).

1200665165520 is an abundant number, since it is smaller than the sum of its proper divisors (2533106598864).

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

1200665165520 is an frugal number, since it uses more digits than its factorization.

1200665165520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7957 (or 4154 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 39.

The spelling of 1200665165520 in words is "one trillion, two hundred billion, six hundred sixty-five million, one hundred sixty-five thousand, five hundred twenty".