13949209 has 2 divisors, whose sum is σ = 13949210. Its totient is φ = 13949208.

The previous prime is 13949207. The next prime is 13949213. The reversal of 13949209 is 90294931.

13949209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9734400 + 4214809 = 3120^2 + 2053^2 .

It is a cyclic number.

It is not a de Polignac number, because 13949209 - 2¹ = 13949207 is a prime.

Together with 13949207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (13949207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6974604 + 6974605.

It is an arithmetic number, because the mean of its divisors is an integer number (6974605).

Almost surely, 2^13949209 is an apocalyptic number.

It is an amenable number.

13949209 is a deficient number, since it is larger than the sum of its proper divisors (1).

13949209 is an equidigital number, since it uses as much as digits as its factorization.

13949209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17496, while the sum is 37.

The square root of 13949209 is about 3734.8639868140. The cubic root of 13949209 is about 240.7224124397.

The spelling of 13949209 in words is "thirteen million, nine hundred forty-nine thousand, two hundred nine".