684694078 has 4 divisors (see below), whose sum is σ = 1027041120. Its totient is φ = 342347038.

The previous prime is 684694067. The next prime is 684694103. The reversal of 684694078 is 870496486.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171173518 + ... + 171173521.

It is an arithmetic number, because the mean of its divisors is an integer number (256760280).

Almost surely, 2^684694078 is an apocalyptic number.

684694078 is a deficient number, since it is larger than the sum of its proper divisors (342347042).

684694078 is a wasteful number, since it uses less digits than its factorization.

684694078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342347041.

The product of its (nonzero) digits is 2322432, while the sum is 52.

The square root of 684694078 is about 26166.6596645426. The cubic root of 684694078 is about 881.3847336340.

The spelling of 684694078 in words is "six hundred eighty-four million, six hundred ninety-four thousand, seventy-eight".