665700012540 has 192 divisors, whose sum is σ = 2118798259200. Its totient is φ = 173464826112.

The previous prime is 665700012529. The next prime is 665700012553. The reversal of 665700012540 is 45210007566.

It is a happy number.

665700012540 is a `hidden beast` number, since 66 + 57 + 0 + 0 + 0 + 1 + 2 + 540 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 665700012495 and 665700012504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5258062 + ... + 5383178.

It is an arithmetic number, because the mean of its divisors is an integer number (11035407600).

Almost surely, 2^665700012540 is an apocalyptic number.

665700012540 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 665700012540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1059399129600).

665700012540 is an abundant number, since it is smaller than the sum of its proper divisors (1453098246660).

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

665700012540 is a wasteful number, since it uses less digits than its factorization.

665700012540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125361 (or 125353 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 36.

The spelling of 665700012540 in words is "six hundred sixty-five billion, seven hundred million, twelve thousand, five hundred forty".