684639512 has 8 divisors (see below), whose sum is σ = 1283699100. Its totient is φ = 342319752.

The previous prime is 684639503. The next prime is 684639523. The reversal of 684639512 is 215936486.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×684639512² = 937462522783196288, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42789962 + ... + 42789977.

Almost surely, 2^684639512 is an apocalyptic number.

It is an amenable number.

684639512 is a deficient number, since it is larger than the sum of its proper divisors (599059588).

684639512 is a wasteful number, since it uses less digits than its factorization.

684639512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85579945 (or 85579941 counting only the distinct ones).

The product of its digits is 311040, while the sum is 44.

The square root of 684639512 is about 26165.6169810689. The cubic root of 684639512 is about 881.3613193246.

The spelling of 684639512 in words is "six hundred eighty-four million, six hundred thirty-nine thousand, five hundred twelve".