684916520 has 16 divisors (see below), whose sum is σ = 1541062260. Its totient is φ = 273966592.

The previous prime is 684916487. The next prime is 684916543. The reversal of 684916520 is 25619486.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 655257604 + 29658916 = 25598^2 + 5446^2 .

It is a super-2 number, since 2×684916520² = 938221278737820800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8561417 + ... + 8561496.

Almost surely, 2^684916520 is an apocalyptic number.

It is an amenable number.

684916520 is an abundant number, since it is smaller than the sum of its proper divisors (856145740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

684916520 is a wasteful number, since it uses less digits than its factorization.

684916520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17122924 (or 17122920 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 41.

The square root of 684916520 is about 26170.9098045903. The cubic root of 684916520 is about 881.4801707844.

The spelling of 684916520 in words is "six hundred eighty-four million, nine hundred sixteen thousand, five hundred twenty".