166990777 has 2 divisors, whose sum is σ = 166990778. Its totient is φ = 166990776.

The previous prime is 166990723. The next prime is 166990783. The reversal of 166990777 is 777099661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84198976 + 82791801 = 9176^2 + 9099^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166990777 is a prime.

It is not a weakly prime, because it can be changed into another prime (166990717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83495388 + 83495389.

It is an arithmetic number, because the mean of its divisors is an integer number (83495389).

Almost surely, 2^166990777 is an apocalyptic number.

It is an amenable number.

166990777 is a deficient number, since it is larger than the sum of its proper divisors (1).

166990777 is an equidigital number, since it uses as much as digits as its factorization.

166990777 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1000188, while the sum is 52.

The square root of 166990777 is about 12922.4911298093. The cubic root of 166990777 is about 550.6777067395.

The spelling of 166990777 in words is "one hundred sixty-six million, nine hundred ninety thousand, seven hundred seventy-seven".