690807609 has 10 divisors (see below), whose sum is σ = 1031947290. Its totient is φ = 460538352.

The previous prime is 690807581. The next prime is 690807617. The reversal of 690807609 is 906708096.

690807609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 689220009 + 1587600 = 26253^2 + 1260^2 .

It is not a de Polignac number, because 690807609 - 2⁹ = 690807097 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (690807659) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 4264164 + ... + 4264325.

It is an arithmetic number, because the mean of its divisors is an integer number (103194729).

Almost surely, 2^690807609 is an apocalyptic number.

It is an amenable number.

690807609 is a deficient number, since it is larger than the sum of its proper divisors (341139681).

690807609 is an equidigital number, since it uses as much as digits as its factorization.

690807609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8528501 (or 8528492 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The square root of 690807609 is about 26283.2191521511. The cubic root of 690807609 is about 884.0002154098. Note that the first 3 decimals are identical.

The spelling of 690807609 in words is "six hundred ninety million, eight hundred seven thousand, six hundred nine".