684739241 has 2 divisors, whose sum is σ = 684739242. Its totient is φ = 684739240.

The previous prime is 684739219. The next prime is 684739333. The reversal of 684739241 is 142937486.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 557951641 + 126787600 = 23621^2 + 11260^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-684739241 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 684739192 and 684739201.

It is not a weakly prime, because it can be changed into another prime (684739201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342369620 + 342369621.

It is an arithmetic number, because the mean of its divisors is an integer number (342369621).

Almost surely, 2^684739241 is an apocalyptic number.

It is an amenable number.

684739241 is a deficient number, since it is larger than the sum of its proper divisors (1).

684739241 is an equidigital number, since it uses as much as digits as its factorization.

684739241 is an evil number, because the sum of its binary digits is even.

The product of its digits is 290304, while the sum is 44.

The square root of 684739241 is about 26167.5226378043. The cubic root of 684739241 is about 881.4041121685.

The spelling of 684739241 in words is "six hundred eighty-four million, seven hundred thirty-nine thousand, two hundred forty-one".