71728180357 has 2 divisors, whose sum is σ = 71728180358. Its totient is φ = 71728180356.

The previous prime is 71728180319. The next prime is 71728180361. The reversal of 71728180357 is 75308182717.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65864602881 + 5863577476 = 256641^2 + 76574^2 .

It is a cyclic number.

It is not a de Polignac number, because 71728180357 - 2⁷ = 71728180229 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71728180357.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71728180157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35864090178 + 35864090179.

It is an arithmetic number, because the mean of its divisors is an integer number (35864090179).

Almost surely, 2^71728180357 is an apocalyptic number.

It is an amenable number.

71728180357 is a deficient number, since it is larger than the sum of its proper divisors (1).

71728180357 is an equidigital number, since it uses as much as digits as its factorization.

71728180357 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 658560, while the sum is 49.

The spelling of 71728180357 in words is "seventy-one billion, seven hundred twenty-eight million, one hundred eighty thousand, three hundred fifty-seven".