690621 has 8 divisors (see below), whose sum is σ = 960960. Its totient is φ = 440352.

The previous prime is 690611. The next prime is 690629. The reversal of 690621 is 126096.

690621 = 273² + 274² + ... + 281².

690621 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 690621 - 2⁵ = 690589 is a prime.

690621 is a modest number, since divided by 621 gives 69 as remainder.

690621 is strictly pandigital in base 7.

690621 is a lucky number.

It is a nialpdrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 690591 and 690600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (690629) 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 in 7 ways as a sum of consecutive naturals, for example, 4936 + ... + 5073.

It is an arithmetic number, because the mean of its divisors is an integer number (120120).

2⁶⁹⁰⁶²¹ is an apocalyptic number.

It is an amenable number.

690621 is a deficient number, since it is larger than the sum of its proper divisors (270339).

690621 is a wasteful number, since it uses less digits than its factorization.

690621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10035.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 690621 is about 831.0361002989. The cubic root of 690621 is about 88.3920609429.

The spelling of 690621 in words is "six hundred ninety thousand, six hundred twenty-one".