684694042 has 4 divisors (see below), whose sum is σ = 1027041066. Its totient is φ = 342347020.

The previous prime is 684694009. The next prime is 684694063. The reversal of 684694042 is 240496486.

684694042 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in only one way, i.e., 665588401 + 19105641 = 25799^2 + 4371^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 684694042.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171173509 + ... + 171173512.

Almost surely, 2^684694042 is an apocalyptic number.

684694042 is a deficient number, since it is larger than the sum of its proper divisors (342347024).

684694042 is a wasteful number, since it uses less digits than its factorization.

684694042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342347023.

The product of its (nonzero) digits is 331776, while the sum is 43.

The square root of 684694042 is about 26166.6589766443. The cubic root of 684694042 is about 881.3847181868.

The spelling of 684694042 in words is "six hundred eighty-four million, six hundred ninety-four thousand, forty-two".