78515138029 has 2 divisors, whose sum is σ = 78515138030. Its totient is φ = 78515138028.

The previous prime is 78515138021. The next prime is 78515138057. The reversal of 78515138029 is 92083151587.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49496015529 + 29019122500 = 222477^2 + 170350^2 .

It is a cyclic number.

It is not a de Polignac number, because 78515138029 - 2³ = 78515138021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78515138021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39257569014 + 39257569015.

It is an arithmetic number, because the mean of its divisors is an integer number (39257569015).

Almost surely, 2^78515138029 is an apocalyptic number.

It is an amenable number.

78515138029 is a deficient number, since it is larger than the sum of its proper divisors (1).

78515138029 is an equidigital number, since it uses as much as digits as its factorization.

78515138029 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 604800, while the sum is 49.

The spelling of 78515138029 in words is "seventy-eight billion, five hundred fifteen million, one hundred thirty-eight thousand, twenty-nine".