665145065491200 has 2160 divisors, whose sum is σ = 2909188082268160. Its totient is φ = 146731253760000.

The previous prime is 665145065491189. The next prime is 665145065491229. The reversal of 665145065491200 is 2194560541566.

It is a happy number.

665145065491200 is a `hidden beast` number, since 6 + 6 + 5 + 1 + 4 + 506 + 5 + 4 + 9 + 120 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2160).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 42634763400 + ... + 42634779000.

Almost surely, 2^{665145065491200} is an apocalyptic number.

665145065491200 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 665145065491200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1454594041134080).

665145065491200 is an abundant number, since it is smaller than the sum of its proper divisors (2244043016776960).

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

665145065491200 is a wasteful number, since it uses less digits than its factorization.

665145065491200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16056 (or 16028 counting only the distinct ones).

The product of its (nonzero) digits is 7776000, while the sum is 54.

The spelling of 665145065491200 in words is "six hundred sixty-five trillion, one hundred forty-five billion, sixty-five million, four hundred ninety-one thousand, two hundred".