646524516640 has 48 divisors (see below), whose sum is σ = 1617262069752. Its totient is φ = 243397464064.

The previous prime is 646524516529. The next prime is 646524516647. The reversal of 646524516640 is 46615425646.

It can be written as a sum of positive squares in 4 ways, for example, as 518901241104 + 127623275536 = 720348^2 + 357244^2 .

It is not an unprimeable number, because it can be changed into a prime (646524516647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 118843699 + ... + 118849138.

Almost surely, 2^646524516640 is an apocalyptic number.

It is an amenable number.

646524516640 is an abundant number, since it is smaller than the sum of its proper divisors (970737553112).

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

646524516640 is a wasteful number, since it uses less digits than its factorization.

646524516640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237692869 (or 237692861 counting only the distinct ones).

The product of its (nonzero) digits is 4147200, while the sum is 49.

The spelling of 646524516640 in words is "six hundred forty-six billion, five hundred twenty-four million, five hundred sixteen thousand, six hundred forty".