644000677 has 2 divisors, whose sum is σ = 644000678. Its totient is φ = 644000676.

The previous prime is 644000657. The next prime is 644000689. The reversal of 644000677 is 776000446.

644000677 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 643839876 + 160801 = 25374^2 + 401^2 .

It is a cyclic number.

It is not a de Polignac number, because 644000677 - 2⁷ = 644000549 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (644000657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322000338 + 322000339.

It is an arithmetic number, because the mean of its divisors is an integer number (322000339).

Almost surely, 2^644000677 is an apocalyptic number.

It is an amenable number.

644000677 is a deficient number, since it is larger than the sum of its proper divisors (1).

644000677 is an equidigital number, since it uses as much as digits as its factorization.

644000677 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28224, while the sum is 34.

The square root of 644000677 is about 25377.1684196642. The cubic root of 644000677 is about 863.5658134553.

The spelling of 644000677 in words is "six hundred forty-four million, six hundred seventy-seven", and thus it is an aban number.