391606681648 has 40 divisors (see below), whose sum is σ = 933831321248. Its totient is φ = 154921324032.

The previous prime is 391606681621. The next prime is 391606681657. The reversal of 391606681648 is 846186606193.

It is a super-2 number, since 2×391606681648² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 391606681592 and 391606681601.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 134478861 + ... + 134481772.

Almost surely, 2^391606681648 is an apocalyptic number.

It is an amenable number.

391606681648 is an abundant number, since it is smaller than the sum of its proper divisors (542224639600).

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

391606681648 is a wasteful number, since it uses less digits than its factorization.

391606681648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268960661 (or 268960655 counting only the distinct ones).

The product of its (nonzero) digits is 8957952, while the sum is 58.

The spelling of 391606681648 in words is "three hundred ninety-one billion, six hundred six million, six hundred eighty-one thousand, six hundred forty-eight".