690309 has 16 divisors (see below), whose sum is σ = 1051840. Its totient is φ = 447120.

The previous prime is 690293. The next prime is 690323. The reversal of 690309 is 903096.

It is not a de Polignac number, because 690309 - 2⁴ = 690293 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a Curzon number.

It is a nialpdrome in base 16.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 690309.

It is not an unprimeable number, because it can be changed into a prime (690509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 654 + ... + 1344.

It is an arithmetic number, because the mean of its divisors is an integer number (65740).

2⁶⁹⁰³⁰⁹ is an apocalyptic number.

It is an amenable number.

690309 is a deficient number, since it is larger than the sum of its proper divisors (361531).

690309 is a wasteful number, since it uses less digits than its factorization.

690309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 737 (or 731 counting only the distinct ones).

The product of its (nonzero) digits is 1458, while the sum is 27.

The square root of 690309 is about 830.8483616160. The cubic root of 690309 is about 88.3787480563.

It can be divided in two parts, 690 and 309, that added together give a palindrome (999).

The spelling of 690309 in words is "six hundred ninety thousand, three hundred nine".