78966813613 has 2 divisors, whose sum is σ = 78966813614. Its totient is φ = 78966813612.

The previous prime is 78966813589. The next prime is 78966813677. The reversal of 78966813613 is 31631866987.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75349152004 + 3617661609 = 274498^2 + 60147^2 .

It is a cyclic number.

It is not a de Polignac number, because 78966813613 - 2⁵ = 78966813581 is a prime.

It is a super-2 number, since 2×78966813613² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78966883613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39483406806 + 39483406807.

It is an arithmetic number, because the mean of its divisors is an integer number (39483406807).

Almost surely, 2^78966813613 is an apocalyptic number.

It is an amenable number.

78966813613 is a deficient number, since it is larger than the sum of its proper divisors (1).

78966813613 is an equidigital number, since it uses as much as digits as its factorization.

78966813613 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7838208, while the sum is 58.

The spelling of 78966813613 in words is "seventy-eight billion, nine hundred sixty-six million, eight hundred thirteen thousand, six hundred thirteen".