646991598548 has 12 divisors (see below), whose sum is σ = 1132241550132. Its totient is φ = 323494012800.

The previous prime is 646991598493. The next prime is 646991598557. The reversal of 646991598548 is 845895199646.

646991598548 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 428891390404 + 218100208144 = 654898^2 + 467012^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 689186 + ... + 1330022.

It is an arithmetic number, because the mean of its divisors is an integer number (94353462511).

Almost surely, 2^646991598548 is an apocalyptic number.

It is an amenable number.

646991598548 is a deficient number, since it is larger than the sum of its proper divisors (485249951584).

646991598548 is a wasteful number, since it uses less digits than its factorization.

646991598548 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 893242 (or 893240 counting only the distinct ones).

The product of its digits is 671846400, while the sum is 74.

The spelling of 646991598548 in words is "six hundred forty-six billion, nine hundred ninety-one million, five hundred ninety-eight thousand, five hundred forty-eight".