66776996160 has 1400 divisors, whose sum is σ = 294413894280. Its totient is φ = 14338695168.

The previous prime is 66776996159. The next prime is 66776996161. The reversal of 66776996160 is 6169967766.

66776996160 is a `hidden beast` number, since 6 + 6 + 7 + 7 + 6 + 9 + 9 + 616 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (66776996159) and next prime (66776996161).

It can be written as a sum of positive squares in 4 ways, for example, as 18931558464 + 47845437696 = 137592^2 + 218736^2 .

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66776996161) by changing a digit.

It is a polite number, since it can be written in 199 ways as a sum of consecutive naturals, for example, 1804783662 + ... + 1804783698.

Almost surely, 2^66776996160 is an apocalyptic number.

66776996160 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 66776996160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147206947140).

66776996160 is an abundant number, since it is smaller than the sum of its proper divisors (227636898120).

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

66776996160 is an equidigital number, since it uses as much as digits as its factorization.

66776996160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123 (or 83 counting only the distinct ones).

The product of its (nonzero) digits is 30862944, while the sum is 63.

The spelling of 66776996160 in words is "sixty-six billion, seven hundred seventy-six million, nine hundred ninety-six thousand, one hundred sixty".