690049609 has 2 divisors, whose sum is σ = 690049610. Its totient is φ = 690049608.

The previous prime is 690049603. The next prime is 690049651. The reversal of 690049609 is 906940096.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 469675584 + 220374025 = 21672^2 + 14845^2 .

It is a cyclic number.

It is not a de Polignac number, because 690049609 - 2⁹ = 690049097 is a prime.

It is not a weakly prime, because it can be changed into another prime (690049603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345024804 + 345024805.

It is an arithmetic number, because the mean of its divisors is an integer number (345024805).

Almost surely, 2^690049609 is an apocalyptic number.

It is an amenable number.

690049609 is a deficient number, since it is larger than the sum of its proper divisors (1).

690049609 is an equidigital number, since it uses as much as digits as its factorization.

690049609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 104976, while the sum is 43.

The square root of 690049609 is about 26268.7953473318. The cubic root of 690049609 is about 883.6767691581.

The spelling of 690049609 in words is "six hundred ninety million, forty-nine thousand, six hundred nine".