77802715643641 has 2 divisors, whose sum is σ = 77802715643642. Its totient is φ = 77802715643640.

The previous prime is 77802715643629. The next prime is 77802715643657. The reversal of 77802715643641 is 14634651720877.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77802631536400 + 84107241 = 8820580^2 + 9171^2 .

It is a cyclic number.

It is not a de Polignac number, because 77802715643641 - 2²³ = 77802707255033 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 77802715643641.

It is not a weakly prime, because it can be changed into another prime (77802715643671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38901357821820 + 38901357821821.

It is an arithmetic number, because the mean of its divisors is an integer number (38901357821821).

Almost surely, 2^{77802715643641} is an apocalyptic number.

It is an amenable number.

77802715643641 is a deficient number, since it is larger than the sum of its proper divisors (1).

77802715643641 is an equidigital number, since it uses as much as digits as its factorization.

77802715643641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 47416320, while the sum is 61.

The spelling of 77802715643641 in words is "seventy-seven trillion, eight hundred two billion, seven hundred fifteen million, six hundred forty-three thousand, six hundred forty-one".