646553628 has 72 divisors (see below), whose sum is σ = 1905976800. Its totient is φ = 184726080.

The previous prime is 646553623. The next prime is 646553629. The reversal of 646553628 is 826355646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646553623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13833 + ... + 38528.

It is an arithmetic number, because the mean of its divisors is an integer number (26471900).

Almost surely, 2^646553628 is an apocalyptic number.

It is an amenable number.

646553628 is an abundant number, since it is smaller than the sum of its proper divisors (1259423172).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

646553628 is a wasteful number, since it uses less digits than its factorization.

646553628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52392 (or 52373 counting only the distinct ones).

The product of its digits is 1036800, while the sum is 45.

The square root of 646553628 is about 25427.4188229950. The cubic root of 646553628 is about 864.7054263303.

The spelling of 646553628 in words is "six hundred forty-six million, five hundred fifty-three thousand, six hundred twenty-eight".