13681709 has 2 divisors, whose sum is σ = 13681710. Its totient is φ = 13681708.

The previous prime is 13681693. The next prime is 13681721. The reversal of 13681709 is 90718631.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10259209 + 3422500 = 3203^2 + 1850^2 .

It is a cyclic number.

It is not a de Polignac number, because 13681709 - 2⁴ = 13681693 is a prime.

It is a super-2 number, since 2×13681709² = 374378322321362, which contains 22 as substring.

It is a Chen prime.

It is equal to p₈₉₀₇₃₈ and since 13681709 and 890738 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13681739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6840854 + 6840855.

It is an arithmetic number, because the mean of its divisors is an integer number (6840855).

Almost surely, 2^13681709 is an apocalyptic number.

It is an amenable number.

13681709 is a deficient number, since it is larger than the sum of its proper divisors (1).

13681709 is an equidigital number, since it uses as much as digits as its factorization.

13681709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 13681709 is about 3698.8794249070. The cubic root of 13681709 is about 239.1737152003.

The spelling of 13681709 in words is "thirteen million, six hundred eighty-one thousand, seven hundred nine".