648420461661 has 32 divisors (see below), whose sum is σ = 1040257699840. Its totient is φ = 350962248384.

The previous prime is 648420461629. The next prime is 648420461707. The reversal of 648420461661 is 166164024846.

It is a happy number.

It is not a de Polignac number, because 648420461661 - 2⁵ = 648420461629 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 648420461661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648420421661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2149971 + ... + 2432943.

It is an arithmetic number, because the mean of its divisors is an integer number (32508053120).

Almost surely, 2^648420461661 is an apocalyptic number.

It is an amenable number.

648420461661 is a deficient number, since it is larger than the sum of its proper divisors (391837238179).

648420461661 is a wasteful number, since it uses less digits than its factorization.

648420461661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288745.

The product of its (nonzero) digits is 1327104, while the sum is 48.

The spelling of 648420461661 in words is "six hundred forty-eight billion, four hundred twenty million, four hundred sixty-one thousand, six hundred sixty-one".