78520320937 has 2 divisors, whose sum is σ = 78520320938. Its totient is φ = 78520320936.

The previous prime is 78520320883. The next prime is 78520320943. The reversal of 78520320937 is 73902302587.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59136998761 + 19383322176 = 243181^2 + 139224^2 .

It is a cyclic number.

It is not a de Polignac number, because 78520320937 - 2¹⁵ = 78520288169 is a prime.

It is not a weakly prime, because it can be changed into another prime (78520320737) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39260160468 + 39260160469.

It is an arithmetic number, because the mean of its divisors is an integer number (39260160469).

Almost surely, 2^78520320937 is an apocalyptic number.

It is an amenable number.

78520320937 is a deficient number, since it is larger than the sum of its proper divisors (1).

78520320937 is an equidigital number, since it uses as much as digits as its factorization.

78520320937 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 635040, while the sum is 46.

The spelling of 78520320937 in words is "seventy-eight billion, five hundred twenty million, three hundred twenty thousand, nine hundred thirty-seven".