680621 has 4 divisors (see below), whose sum is σ = 682272. Its totient is φ = 678972.

The previous prime is 680611. The next prime is 680623. The reversal of 680621 is 126086.

680621 is digitally balanced in base 2, 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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 680621 - 2¹⁰ = 679597 is a prime.

It is a Duffinian number.

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 680621.

It is not an unprimeable number, because it can be changed into a prime (680623) 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, 410 + ... + 1236.

It is an arithmetic number, because the mean of its divisors is an integer number (170568).

2⁶⁸⁰⁶²¹ is an apocalyptic number.

It is an amenable number.

680621 is a deficient number, since it is larger than the sum of its proper divisors (1651).

680621 is an equidigital number, since it uses as much as digits as its factorization.

680621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1650.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 680621 is about 824.9975757540. The cubic root of 680621 is about 87.9633542321.

The spelling of 680621 in words is "six hundred eighty thousand, six hundred twenty-one".