684404123 has 16 divisors (see below), whose sum is σ = 771064896. Its totient is φ = 602743680.

The previous prime is 684404101. The next prime is 684404131. The reversal of 684404123 is 321404486.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-684404123 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 684404123.

It is not an unprimeable number, because it can be changed into a prime (684404153) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 123161 + ... + 128597.

It is an arithmetic number, because the mean of its divisors is an integer number (48191556).

Almost surely, 2^684404123 is an apocalyptic number.

684404123 is a deficient number, since it is larger than the sum of its proper divisors (86660773).

684404123 is a wasteful number, since it uses less digits than its factorization.

684404123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5894.

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 684404123 is about 26161.1185349556. The cubic root of 684404123 is about 881.2602994756.

The spelling of 684404123 in words is "six hundred eighty-four million, four hundred four thousand, one hundred twenty-three".