690321 has 4 divisors (see below), whose sum is σ = 920432. Its totient is φ = 460212.

The previous prime is 690293. The next prime is 690323. The reversal of 690321 is 123096.

690321 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 690321 - 2¹⁸ = 428177 is a prime.

It is a D-number.

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

It is a Duffinian number.

690321 is strictly pandigital in base 7.

It is not an unprimeable number, because it can be changed into a prime (690323) 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 3 ways as a sum of consecutive naturals, for example, 115051 + ... + 115056.

It is an arithmetic number, because the mean of its divisors is an integer number (230108).

2⁶⁹⁰³²¹ is an apocalyptic number.

It is an amenable number.

690321 is a deficient number, since it is larger than the sum of its proper divisors (230111).

690321 is a wasteful number, since it uses less digits than its factorization.

690321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230110.

The product of its (nonzero) digits is 324, while the sum is 21.

The square root of 690321 is about 830.8555831190. The cubic root of 690321 is about 88.3792601646.

The spelling of 690321 in words is "six hundred ninety thousand, three hundred twenty-one".