13958209 has 2 divisors, whose sum is σ = 13958210. Its totient is φ = 13958208.

The previous prime is 13958149. The next prime is 13958221. The reversal of 13958209 is 90285931.

13958209 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12759184 + 1199025 = 3572^2 + 1095^2 .

It is a cyclic number.

It is not a de Polignac number, because 13958209 - 2¹⁵ = 13925441 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (13958249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6979104 + 6979105.

It is an arithmetic number, because the mean of its divisors is an integer number (6979105).

Almost surely, 2^13958209 is an apocalyptic number.

It is an amenable number.

13958209 is a deficient number, since it is larger than the sum of its proper divisors (1).

13958209 is an equidigital number, since it uses as much as digits as its factorization.

13958209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 13958209 is about 3736.0686556861. The cubic root of 13958209 is about 240.7741725058.

It can be divided in two parts, 1395 and 8209, that added together give a square (9604 = 98²).

The spelling of 13958209 in words is "thirteen million, nine hundred fifty-eight thousand, two hundred nine".