648666404666847 has 24 divisors (see below), whose sum is σ = 1091018427261984. Its totient is φ = 363672809083584.

The previous prime is 648666404666827. The next prime is 648666404666869. The reversal of 648666404666847 is 748666404666846.

It is not a de Polignac number, because 648666404666847 - 2¹⁸ = 648666404404703 is a prime.

It is a super-2 number, since 2×648666404666847² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648666404666827) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 97134828148 + ... + 97134834825.

It is an arithmetic number, because the mean of its divisors is an integer number (45459101135916).

Almost surely, 2^{648666404666847} is an apocalyptic number.

648666404666847 is a deficient number, since it is larger than the sum of its proper divisors (442352022595137).

648666404666847 is a wasteful number, since it uses less digits than its factorization.

648666404666847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194269663039 (or 194269663036 counting only the distinct ones).

The product of its (nonzero) digits is 32105299968, while the sum is 81.

Subtracting 648666404666847 from its reverse (748666404666846), we obtain a palindrome (99999999999999).

The spelling of 648666404666847 in words is "six hundred forty-eight trillion, six hundred sixty-six billion, four hundred four million, six hundred sixty-six thousand, eight hundred forty-seven".