676721 has 2 divisors, whose sum is σ = 676722. Its totient is φ = 676720.

The previous prime is 676717. The next prime is 676727. The reversal of 676721 is 127676.

676721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 583696 + 93025 = 764^2 + 305^2 .

It is a cyclic number.

It is not a de Polignac number, because 676721 - 2² = 676717 is a prime.

It is a Chen prime.

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

It is not a weakly prime, because it can be changed into another prime (676727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 338360 + 338361.

It is an arithmetic number, because the mean of its divisors is an integer number (338361).

2⁶⁷⁶⁷²¹ is an apocalyptic number.

It is an amenable number.

676721 is a deficient number, since it is larger than the sum of its proper divisors (1).

676721 is an equidigital number, since it uses as much as digits as its factorization.

676721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3528, while the sum is 29.

The square root of 676721 is about 822.6305367539. The cubic root of 676721 is about 87.7950204989.

The spelling of 676721 in words is "six hundred seventy-six thousand, seven hundred twenty-one".