66786309752085 has 512 divisors, whose sum is σ = 161255697039360. Its totient is φ = 25371906048000.

The previous prime is 66786309752069. The next prime is 66786309752089. The reversal of 66786309752085 is 58025790368766.

It is a happy number.

66786309752085 is a `hidden beast` number, since 6 + 6 + 7 + 8 + 6 + 3 + 0 + 97 + 520 + 8 + 5 = 666.

It is not a de Polignac number, because 66786309752085 - 2⁴ = 66786309752069 is a prime.

It is a super-2 number, since 2×66786309752085² (a number of 28 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66786309752089) by changing a digit.

It is a polite number, since it can be written in 511 ways as a sum of consecutive naturals, for example, 3838064385 + ... + 3838081785.

It is an arithmetic number, because the mean of its divisors is an integer number (314952533280).

Almost surely, 2^{66786309752085} is an apocalyptic number.

It is an amenable number.

66786309752085 is an abundant number, since it is smaller than the sum of its proper divisors (94469387287275).

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

66786309752085 is a wasteful number, since it uses less digits than its factorization.

66786309752085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18074 (or 18068 counting only the distinct ones).

The product of its (nonzero) digits is 914457600, while the sum is 72.

The spelling of 66786309752085 in words is "sixty-six trillion, seven hundred eighty-six billion, three hundred nine million, seven hundred fifty-two thousand, eighty-five".