643646325 has 48 divisors (see below), whose sum is σ = 1230921216. Its totient is φ = 290673600.

The previous prime is 643646323. The next prime is 643646357. The reversal of 643646325 is 523646346.

It is not a de Polignac number, because 643646325 - 2¹ = 643646323 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643646323) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 36190 + ... + 50960.

It is an arithmetic number, because the mean of its divisors is an integer number (25644192).

Almost surely, 2^643646325 is an apocalyptic number.

It is an amenable number.

643646325 is a deficient number, since it is larger than the sum of its proper divisors (587274891).

643646325 is a wasteful number, since it uses less digits than its factorization.

643646325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14874 (or 14869 counting only the distinct ones).

The product of its digits is 311040, while the sum is 39.

The square root of 643646325 is about 25370.1857502069. The cubic root of 643646325 is about 863.4073962225.

The spelling of 643646325 in words is "six hundred forty-three million, six hundred forty-six thousand, three hundred twenty-five".