684978454663 has 4 divisors (see below), whose sum is σ = 686504019600. Its totient is φ = 683452889728.

The previous prime is 684978454591. The next prime is 684978454679. The reversal of 684978454663 is 366454879486.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 684978454663 - 2⁹ = 684978454151 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 684978454592 and 684978454601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684978454463) 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 3 ways as a sum of consecutive naturals, for example, 762781795 + ... + 762782692.

It is an arithmetic number, because the mean of its divisors is an integer number (171626004900).

Almost surely, 2^684978454663 is an apocalyptic number.

684978454663 is a deficient number, since it is larger than the sum of its proper divisors (1525564937).

684978454663 is a wasteful number, since it uses less digits than its factorization.

684978454663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1525564936.

The product of its digits is 836075520, while the sum is 70.

The spelling of 684978454663 in words is "six hundred eighty-four billion, nine hundred seventy-eight million, four hundred fifty-four thousand, six hundred sixty-three".