66706765650 has 192 divisors, whose sum is σ = 216850882560. Its totient is φ = 14755348800.

The previous prime is 66706765639. The next prime is 66706765651. The reversal of 66706765650 is 5656760766.

66706765650 is a `hidden beast` number, since 6 + 6 + 7 + 0 + 6 + 76 + 565 + 0 = 666.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66706765651) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 179097 + ... + 406803.

It is an arithmetic number, because the mean of its divisors is an integer number (1129431680).

Almost surely, 2^66706765650 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66706765650, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108425441280).

66706765650 is an abundant number, since it is smaller than the sum of its proper divisors (150144116910).

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

66706765650 is a wasteful number, since it uses less digits than its factorization.

66706765650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227766 (or 227755 counting only the distinct ones).

The product of its (nonzero) digits is 9525600, while the sum is 54.

The spelling of 66706765650 in words is "sixty-six billion, seven hundred six million, seven hundred sixty-five thousand, six hundred fifty".