16660777277 has 2 divisors, whose sum is σ = 16660777278. Its totient is φ = 16660777276.

The previous prime is 16660777271. The next prime is 16660777279. The reversal of 16660777277 is 77277706661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16283291236 + 377486041 = 127606^2 + 19429^2 .

It is a cyclic number.

It is not a de Polignac number, because 16660777277 - 2¹⁶ = 16660711741 is a prime.

Together with 16660777279, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16660777271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8330388638 + 8330388639.

It is an arithmetic number, because the mean of its divisors is an integer number (8330388639).

Almost surely, 2^16660777277 is an apocalyptic number.

It is an amenable number.

16660777277 is a deficient number, since it is larger than the sum of its proper divisors (1).

16660777277 is an equidigital number, since it uses as much as digits as its factorization.

16660777277 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7260624, while the sum is 56.

The spelling of 16660777277 in words is "sixteen billion, six hundred sixty million, seven hundred seventy-seven thousand, two hundred seventy-seven".