646704648 has 132 divisors (see below), whose sum is σ = 1869333165. Its totient is φ = 209742048.

The previous prime is 646704629. The next prime is 646704673. The reversal of 646704648 is 846407646.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 521756964 + 124947684 = 22842^2 + 11178^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=17982.

It is an unprimeable number.

It is a polite number, since it can be written in 32 ways as a sum of consecutive naturals, for example, 17478486 + ... + 17478522.

Almost surely, 2^646704648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646704648

646704648 is an abundant number, since it is smaller than the sum of its proper divisors (1222628517).

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

646704648 is an frugal number, since it uses more digits than its factorization.

646704648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110 (or 42 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 45.

The square root of 646704648 is about 25430.3882785930. The cubic root of 646704648 is about 864.7727461636.

The spelling of 646704648 in words is "six hundred forty-six million, seven hundred four thousand, six hundred forty-eight".