646446625 has 32 divisors (see below), whose sum is σ = 918418176. Its totient is φ = 449680000.

The previous prime is 646446623. The next prime is 646446629. The reversal of 646446625 is 526644646.

It is not a de Polignac number, because 646446625 - 2¹ = 646446623 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646446623) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21405 + ... + 41845.

It is an arithmetic number, because the mean of its divisors is an integer number (28700568).

Almost surely, 2^646446625 is an apocalyptic number.

It is an amenable number.

646446625 is a deficient number, since it is larger than the sum of its proper divisors (271971551).

646446625 is a wasteful number, since it uses less digits than its factorization.

646446625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20490 (or 20480 counting only the distinct ones).

The product of its digits is 829440, while the sum is 43.

The square root of 646446625 is about 25425.3146489871. The cubic root of 646446625 is about 864.6577215071.

The spelling of 646446625 in words is "six hundred forty-six million, four hundred forty-six thousand, six hundred twenty-five".