644082325 has 12 divisors (see below), whose sum is σ = 818142948. Its totient is φ = 502697600.

The previous prime is 644082293. The next prime is 644082359. The reversal of 644082325 is 523280446.

It can be written as a sum of positive squares in 6 ways, for example, as 234181809 + 409900516 = 15303^2 + 20246^2 .

It is not a de Polignac number, because 644082325 - 2⁵ = 644082293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 313162 + ... + 315211.

It is an arithmetic number, because the mean of its divisors is an integer number (68178579).

Almost surely, 2^644082325 is an apocalyptic number.

It is an amenable number.

644082325 is a deficient number, since it is larger than the sum of its proper divisors (174060623).

644082325 is a wasteful number, since it uses less digits than its factorization.

644082325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 628424 (or 628419 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 34.

The square root of 644082325 is about 25378.7770587946. Note that the first 3 decimals coincide. The cubic root of 644082325 is about 863.6023069169.

The spelling of 644082325 in words is "six hundred forty-four million, eighty-two thousand, three hundred twenty-five".