684840518943 has 16 divisors (see below), whose sum is σ = 1043649659136. Its totient is φ = 391306256640.

The previous prime is 684840518939. The next prime is 684840518963. The reversal of 684840518943 is 349815048486.

It is a happy number.

It is not a de Polignac number, because 684840518943 - 2² = 684840518939 is a prime.

It is a super-2 number, since 2×684840518943² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684840518963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1028146 + ... + 1557807.

It is an arithmetic number, because the mean of its divisors is an integer number (65228103696).

Almost surely, 2^684840518943 is an apocalyptic number.

684840518943 is a deficient number, since it is larger than the sum of its proper divisors (358809140193).

684840518943 is a wasteful number, since it uses less digits than its factorization.

684840518943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2598574.

The product of its (nonzero) digits is 26542080, while the sum is 60.

The spelling of 684840518943 in words is "six hundred eighty-four billion, eight hundred forty million, five hundred eighteen thousand, nine hundred forty-three".