684662864 has 10 divisors (see below), whose sum is σ = 1326534330. Its totient is φ = 342331424.

The previous prime is 684662861. The next prime is 684662921. The reversal of 684662864 is 468266486.

It can be written as a sum of positive squares in only one way, i.e., 466214464 + 218448400 = 21592^2 + 14780^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684662861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21395699 + ... + 21395730.

It is an arithmetic number, because the mean of its divisors is an integer number (132653433).

Almost surely, 2^684662864 is an apocalyptic number.

It is an amenable number.

684662864 is a deficient number, since it is larger than the sum of its proper divisors (641871466).

684662864 is a wasteful number, since it uses less digits than its factorization.

684662864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42791437 (or 42791431 counting only the distinct ones).

The product of its digits is 2654208, while the sum is 50.

The square root of 684662864 is about 26166.0632117252. The cubic root of 684662864 is about 881.3713398367.

The spelling of 684662864 in words is "six hundred eighty-four million, six hundred sixty-two thousand, eight hundred sixty-four".