684336749 has 6 divisors (see below), whose sum is σ = 707125230. Its totient is φ = 662260440.

The previous prime is 684336721. The next prime is 684336761. The reversal of 684336749 is 947633486.

It can be written as a sum of positive squares in only one way, i.e., 670033225 + 14303524 = 25885^2 + 3782^2 .

It is not a de Polignac number, because 684336749 - 2⁸ = 684336493 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 684336697 and 684336706.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684336449) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 355094 + ... + 357015.

It is an arithmetic number, because the mean of its divisors is an integer number (117854205).

Almost surely, 2^684336749 is an apocalyptic number.

It is an amenable number.

684336749 is a deficient number, since it is larger than the sum of its proper divisors (22788481).

684336749 is an equidigital number, since it uses as much as digits as its factorization.

684336749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712171 (or 712140 counting only the distinct ones).

The product of its digits is 2612736, while the sum is 50.

The square root of 684336749 is about 26159.8308289637. The cubic root of 684336749 is about 881.2313808986.

The spelling of 684336749 in words is "six hundred eighty-four million, three hundred thirty-six thousand, seven hundred forty-nine".