71216777 has 2 divisors, whose sum is σ = 71216778. Its totient is φ = 71216776.

The previous prime is 71216773. The next prime is 71216813. The reversal of 71216777 is 77761217.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38738176 + 32478601 = 6224^2 + 5699^2 .

It is an emirp because it is prime and its reverse (77761217) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71216777 - 2² = 71216773 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71216777.

It is not a weakly prime, because it can be changed into another prime (71216771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35608388 + 35608389.

It is an arithmetic number, because the mean of its divisors is an integer number (35608389).

Almost surely, 2^71216777 is an apocalyptic number.

It is an amenable number.

71216777 is a deficient number, since it is larger than the sum of its proper divisors (1).

71216777 is an equidigital number, since it uses as much as digits as its factorization.

71216777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 28812, while the sum is 38.

The square root of 71216777 is about 8439.0033179280. The cubic root of 71216777 is about 414.5027712073.

The spelling of 71216777 in words is "seventy-one million, two hundred sixteen thousand, seven hundred seventy-seven".