78425979829 has 2 divisors, whose sum is σ = 78425979830. Its totient is φ = 78425979828.

The previous prime is 78425979767. The next prime is 78425979859. The reversal of 78425979829 is 92897952487.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66674986225 + 11750993604 = 258215^2 + 108402^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78425979829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78425979859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39212989914 + 39212989915.

It is an arithmetic number, because the mean of its divisors is an integer number (39212989915).

Almost surely, 2^78425979829 is an apocalyptic number.

It is an amenable number.

78425979829 is a deficient number, since it is larger than the sum of its proper divisors (1).

78425979829 is an equidigital number, since it uses as much as digits as its factorization.

78425979829 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 182891520, while the sum is 70.

The spelling of 78425979829 in words is "seventy-eight billion, four hundred twenty-five million, nine hundred seventy-nine thousand, eight hundred twenty-nine".