18856985075777 has 2 divisors, whose sum is σ = 18856985075778. Its totient is φ = 18856985075776.

The previous prime is 18856985075711. The next prime is 18856985075779. The reversal of 18856985075777 is 77757058965881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18168045235201 + 688939840576 = 4262399^2 + 830024^2 .

It is a cyclic number.

It is not a de Polignac number, because 18856985075777 - 2¹⁸ = 18856984813633 is a prime.

It is a super-2 number, since 2×18856985075777² (a number of 27 digits) contains 22 as substring.

Together with 18856985075779, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 18856985075695 and 18856985075704.

It is not a weakly prime, because it can be changed into another prime (18856985075779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9428492537888 + 9428492537889.

It is an arithmetic number, because the mean of its divisors is an integer number (9428492537889).

Almost surely, 2^{18856985075777} is an apocalyptic number.

It is an amenable number.

18856985075777 is a deficient number, since it is larger than the sum of its proper divisors (1).

18856985075777 is an equidigital number, since it uses as much as digits as its factorization.

18856985075777 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8297856000, while the sum is 83.

The spelling of 18856985075777 in words is "eighteen trillion, eight hundred fifty-six billion, nine hundred eighty-five million, seventy-five thousand, seven hundred seventy-seven".