78526025521 has 2 divisors, whose sum is σ = 78526025522. Its totient is φ = 78526025520.

The previous prime is 78526025401. The next prime is 78526025531. The reversal of 78526025521 is 12552062587.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72703572496 + 5822453025 = 269636^2 + 76305^2 .

It is a cyclic number.

It is not a de Polignac number, because 78526025521 - 2¹¹ = 78526023473 is a prime.

It is not a weakly prime, because it can be changed into another prime (78526025531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39263012760 + 39263012761.

It is an arithmetic number, because the mean of its divisors is an integer number (39263012761).

Almost surely, 2^78526025521 is an apocalyptic number.

It is an amenable number.

78526025521 is a deficient number, since it is larger than the sum of its proper divisors (1).

78526025521 is an equidigital number, since it uses as much as digits as its factorization.

78526025521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336000, while the sum is 43.

The spelling of 78526025521 in words is "seventy-eight billion, five hundred twenty-six million, twenty-five thousand, five hundred twenty-one".