13729257 has 28 divisors (see below), whose sum is σ = 21182340. Its totient is φ = 8887968.

The previous prime is 13729223. The next prime is 13729291. The reversal of 13729257 is 75292731.

It is an interprime number because it is at equal distance from previous prime (13729223) and next prime (13729291).

It can be written as a sum of positive squares in 2 ways, for example, as 11758041 + 1971216 = 3429^2 + 1404^2 .

It is not a de Polignac number, because 13729257 - 2⁷ = 13729129 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13729207) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 26719 + ... + 27227.

Almost surely, 2^13729257 is an apocalyptic number.

It is an amenable number.

13729257 is a deficient number, since it is larger than the sum of its proper divisors (7453083).

13729257 is an frugal number, since it uses more digits than its factorization.

13729257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 564 (or 549 counting only the distinct ones).

The product of its digits is 26460, while the sum is 36.

The square root of 13729257 is about 3705.3012023316. The cubic root of 13729257 is about 239.4504614076.

The spelling of 13729257 in words is "thirteen million, seven hundred twenty-nine thousand, two hundred fifty-seven".