77996173261 has 2 divisors, whose sum is σ = 77996173262. Its totient is φ = 77996173260.

The previous prime is 77996173237. The next prime is 77996173289. The reversal of 77996173261 is 16237169977.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65715322500 + 12280850761 = 256350^2 + 110819^2 .

It is a cyclic number.

It is not a de Polignac number, because 77996173261 - 2⁷ = 77996173133 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 77996173196 and 77996173205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77996173201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38998086630 + 38998086631.

It is an arithmetic number, because the mean of its divisors is an integer number (38998086631).

Almost surely, 2^77996173261 is an apocalyptic number.

It is an amenable number.

77996173261 is a deficient number, since it is larger than the sum of its proper divisors (1).

77996173261 is an equidigital number, since it uses as much as digits as its factorization.

77996173261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6001128, while the sum is 58.

The spelling of 77996173261 in words is "seventy-seven billion, nine hundred ninety-six million, one hundred seventy-three thousand, two hundred sixty-one".