77802738335981 has 2 divisors, whose sum is σ = 77802738335982. Its totient is φ = 77802738335980.

The previous prime is 77802738335953. The next prime is 77802738336019. The reversal of 77802738335981 is 18953383720877.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52419178331881 + 25383560004100 = 7240109^2 + 5038210^2 .

It is a cyclic number.

It is not a de Polignac number, because 77802738335981 - 2²⁶ = 77802671227117 is a prime.

It is a super-2 number, since 2×77802738335981² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77802738335921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38901369167990 + 38901369167991.

It is an arithmetic number, because the mean of its divisors is an integer number (38901369167991).

Almost surely, 2^{77802738335981} is an apocalyptic number.

It is an amenable number.

77802738335981 is a deficient number, since it is larger than the sum of its proper divisors (1).

77802738335981 is an equidigital number, since it uses as much as digits as its factorization.

77802738335981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 426746880, while the sum is 71.

The spelling of 77802738335981 in words is "seventy-seven trillion, eight hundred two billion, seven hundred thirty-eight million, three hundred thirty-five thousand, nine hundred eighty-one".