78213725328704 has 98 divisors (see below), whose sum is σ = 181072718960010. Its totient is φ = 33520164771072.

The previous prime is 78213725328623. The next prime is 78213725328707. The reversal of 78213725328704 is 40782352731287.

It can be written as a sum of positive squares in only one way, i.e., 42757893258304 + 35455832070400 = 6538952^2 + 5954480^2 .

It is a tau number, because it is divible by the number of its divisors (98).

It is a super-2 number, since 2×78213725328704² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78213725328707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 2335742 + ... + 12723330.

Almost surely, 2^{78213725328704} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78213725328704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90536359480005).

78213725328704 is an abundant number, since it is smaller than the sum of its proper divisors (102858993631306).

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

78213725328704 is an frugal number, since it uses more digits than its factorization.

78213725328704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10387643 (or 10387598 counting only the distinct ones).

The product of its (nonzero) digits is 31610880, while the sum is 59.

The spelling of 78213725328704 in words is "seventy-eight trillion, two hundred thirteen billion, seven hundred twenty-five million, three hundred twenty-eight thousand, seven hundred four".