78505107481 has 2 divisors, whose sum is σ = 78505107482. Its totient is φ = 78505107480.

The previous prime is 78505107433. The next prime is 78505107487. The reversal of 78505107481 is 18470150587.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77941472400 + 563635081 = 279180^2 + 23741^2 .

It is a cyclic number.

It is not a de Polignac number, because 78505107481 - 2³³ = 69915172889 is a prime.

It is a super-2 number, since 2×78505107481² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78505107487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39252553740 + 39252553741.

It is an arithmetic number, because the mean of its divisors is an integer number (39252553741).

Almost surely, 2^78505107481 is an apocalyptic number.

It is an amenable number.

78505107481 is a deficient number, since it is larger than the sum of its proper divisors (1).

78505107481 is an equidigital number, since it uses as much as digits as its factorization.

78505107481 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 313600, while the sum is 46.

The spelling of 78505107481 in words is "seventy-eight billion, five hundred five million, one hundred seven thousand, four hundred eighty-one".