71780212957 has 2 divisors, whose sum is σ = 71780212958. Its totient is φ = 71780212956.

The previous prime is 71780212927. The next prime is 71780212963. The reversal of 71780212957 is 75921208717.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55479562681 + 16300650276 = 235541^2 + 127674^2 .

It is a cyclic number.

It is not a de Polignac number, because 71780212957 - 2³⁵ = 37420474589 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71780212957.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71780212927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35890106478 + 35890106479.

It is an arithmetic number, because the mean of its divisors is an integer number (35890106479).

Almost surely, 2^71780212957 is an apocalyptic number.

It is an amenable number.

71780212957 is a deficient number, since it is larger than the sum of its proper divisors (1).

71780212957 is an equidigital number, since it uses as much as digits as its factorization.

71780212957 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 493920, while the sum is 49.

The spelling of 71780212957 in words is "seventy-one billion, seven hundred eighty million, two hundred twelve thousand, nine hundred fifty-seven".