660799109 has 2 divisors, whose sum is σ = 660799110. Its totient is φ = 660799108.

The previous prime is 660799079. The next prime is 660799123. The reversal of 660799109 is 901997066.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 569061025 + 91738084 = 23855^2 + 9578^2 .

It is a cyclic number.

It is not a de Polignac number, because 660799109 - 2¹² = 660795013 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (660799159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330399554 + 330399555.

It is an arithmetic number, because the mean of its divisors is an integer number (330399555).

Almost surely, 2^660799109 is an apocalyptic number.

It is an amenable number.

660799109 is a deficient number, since it is larger than the sum of its proper divisors (1).

660799109 is an equidigital number, since it uses as much as digits as its factorization.

660799109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 183708, while the sum is 47.

The square root of 660799109 is about 25706.0130903258. The cubic root of 660799109 is about 871.0100169196.

The spelling of 660799109 in words is "six hundred sixty million, seven hundred ninety-nine thousand, one hundred nine".