669777109 has 2 divisors, whose sum is σ = 669777110. Its totient is φ = 669777108.

The previous prime is 669777083. The next prime is 669777211. The reversal of 669777109 is 901777966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 447111025 + 222666084 = 21145^2 + 14922^2 .

It is a cyclic number.

It is not a de Polignac number, because 669777109 - 2⁷ = 669776981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (669772109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334888554 + 334888555.

It is an arithmetic number, because the mean of its divisors is an integer number (334888555).

Almost surely, 2^669777109 is an apocalyptic number.

It is an amenable number.

669777109 is a deficient number, since it is larger than the sum of its proper divisors (1).

669777109 is an equidigital number, since it uses as much as digits as its factorization.

669777109 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 669777109 is about 25880.0523376596. The cubic root of 669777109 is about 874.9369680854.

The spelling of 669777109 in words is "six hundred sixty-nine million, seven hundred seventy-seven thousand, one hundred nine".