690823 has 4 divisors (see below), whose sum is σ = 789520. Its totient is φ = 592128.

The previous prime is 690817. The next prime is 690839. The reversal of 690823 is 328096.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-690823 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 690791 and 690800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (690323) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49338 + ... + 49351.

It is an arithmetic number, because the mean of its divisors is an integer number (197380).

2⁶⁹⁰⁸²³ is an apocalyptic number.

690823 is a deficient number, since it is larger than the sum of its proper divisors (98697).

690823 is an equidigital number, since it uses as much as digits as its factorization.

690823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98696.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 690823 is about 831.1576264464. The cubic root of 690823 is about 88.4006780453.

The spelling of 690823 in words is "six hundred ninety thousand, eight hundred twenty-three".