216677776657 has 2 divisors, whose sum is σ = 216677776658. Its totient is φ = 216677776656.

The previous prime is 216677776597. The next prime is 216677776663. The reversal of 216677776657 is 756677776612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 187631050896 + 29046725761 = 433164^2 + 170431^2 .

It is a cyclic number.

It is not a de Polignac number, because 216677776657 - 2⁷ = 216677776529 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 216677776592 and 216677776601.

It is not a weakly prime, because it can be changed into another prime (216677776697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108338888328 + 108338888329.

It is an arithmetic number, because the mean of its divisors is an integer number (108338888329).

Almost surely, 2^216677776657 is an apocalyptic number.

It is an amenable number.

216677776657 is a deficient number, since it is larger than the sum of its proper divisors (1).

216677776657 is an equidigital number, since it uses as much as digits as its factorization.

216677776657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217818720, while the sum is 67.

The spelling of 216677776657 in words is "two hundred sixteen billion, six hundred seventy-seven million, seven hundred seventy-six thousand, six hundred fifty-seven".