11291209 has 2 divisors, whose sum is σ = 11291210. Its totient is φ = 11291208.

The previous prime is 11291177. The next prime is 11291219. The reversal of 11291209 is 90219211.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10705984 + 585225 = 3272^2 + 765^2 .

It is a cyclic number.

It is not a de Polignac number, because 11291209 - 2⁵ = 11291177 is a prime.

It is not a weakly prime, because it can be changed into another prime (11291219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5645604 + 5645605.

It is an arithmetic number, because the mean of its divisors is an integer number (5645605).

Almost surely, 2^11291209 is an apocalyptic number.

It is an amenable number.

11291209 is a deficient number, since it is larger than the sum of its proper divisors (1).

11291209 is an equidigital number, since it uses as much as digits as its factorization.

11291209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 25.

The square root of 11291209 is about 3360.2394259933. The cubic root of 11291209 is about 224.3434953684.

The spelling of 11291209 in words is "eleven million, two hundred ninety-one thousand, two hundred nine".