684322681 has 12 divisors (see below), whose sum is σ = 804261108. Its totient is φ = 580511232.

The previous prime is 684322669. The next prime is 684322687. The reversal of 684322681 is 186223486.

It can be written as a sum of positive squares in 2 ways, for example, as 495507600 + 188815081 = 22260^2 + 13741^2 .

It is not a de Polignac number, because 684322681 - 2⁵ = 684322649 is a prime.

It is a super-2 number, since 2×684322681² = 936595063462055522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (684322687) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 67236 + ... + 76741.

It is an arithmetic number, because the mean of its divisors is an integer number (67021759).

Almost surely, 2^684322681 is an apocalyptic number.

It is an amenable number.

684322681 is a deficient number, since it is larger than the sum of its proper divisors (119938427).

684322681 is a wasteful number, since it uses less digits than its factorization.

684322681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144088 (or 144081 counting only the distinct ones).

The product of its digits is 110592, while the sum is 40.

The square root of 684322681 is about 26159.5619420509. The cubic root of 684322681 is about 881.2253423277.

The spelling of 684322681 in words is "six hundred eighty-four million, three hundred twenty-two thousand, six hundred eighty-one".