78122148613 has 4 divisors (see below), whose sum is σ = 78446307148. Its totient is φ = 77797990080.

The previous prime is 78122148607. The next prime is 78122148623. The reversal of 78122148613 is 31684122187.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31684122187 = 5953 ⋅5322379.

It can be written as a sum of positive squares in 2 ways, for example, as 59739669889 + 18382478724 = 244417^2 + 135582^2 .

It is a cyclic number.

It is not a de Polignac number, because 78122148613 - 2⁹ = 78122148101 is a prime.

It is a super-2 number, since 2×78122148613² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78122148613.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78122148623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 162078906 + ... + 162079387.

It is an arithmetic number, because the mean of its divisors is an integer number (19611576787).

Almost surely, 2^78122148613 is an apocalyptic number.

It is an amenable number.

78122148613 is a deficient number, since it is larger than the sum of its proper divisors (324158535).

78122148613 is a wasteful number, since it uses less digits than its factorization.

78122148613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324158534.

The product of its digits is 129024, while the sum is 43.

The spelling of 78122148613 in words is "seventy-eight billion, one hundred twenty-two million, one hundred forty-eight thousand, six hundred thirteen".