66779100864 has 1120 divisors, whose sum is σ = 254920089600. Its totient is φ = 16860856320.

The previous prime is 66779100827. The next prime is 66779100881. The reversal of 66779100864 is 46800197766.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 66779100864.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 750326932 + ... + 750327020.

Almost surely, 2^66779100864 is an apocalyptic number.

66779100864 is a gapful number since it is divisible by the number (64) 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 66779100864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127460044800).

66779100864 is an abundant number, since it is smaller than the sum of its proper divisors (188140988736).

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

66779100864 is a wasteful number, since it uses less digits than its factorization.

66779100864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 3048192, while the sum is 54.

The spelling of 66779100864 in words is "sixty-six billion, seven hundred seventy-nine million, one hundred thousand, eight hundred sixty-four".