690165449 has 2 divisors, whose sum is σ = 690165450. Its totient is φ = 690165448.

The previous prime is 690165391. The next prime is 690165451. The reversal of 690165449 is 944561096.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 406748224 + 283417225 = 20168^2 + 16835^2 .

It is a cyclic number.

It is not a de Polignac number, because 690165449 - 2⁸ = 690165193 is a prime.

It is a super-3 number, since 3×690165449³ (a number of 27 digits) contains 333 as substring.

It is a Sophie Germain prime.

Together with 690165451, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (690165149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345082724 + 345082725.

It is an arithmetic number, because the mean of its divisors is an integer number (345082725).

Almost surely, 2^690165449 is an apocalyptic number.

It is an amenable number.

690165449 is a deficient number, since it is larger than the sum of its proper divisors (1).

690165449 is an equidigital number, since it uses as much as digits as its factorization.

690165449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 233280, while the sum is 44.

The square root of 690165449 is about 26271.0001522591. Note that the first 3 decimals coincide. The cubic root of 690165449 is about 883.7262145835.

The spelling of 690165449 in words is "six hundred ninety million, one hundred sixty-five thousand, four hundred forty-nine".