11949809 has 2 divisors, whose sum is σ = 11949810. Its totient is φ = 11949808.

The previous prime is 11949799. The next prime is 11949851. The reversal of 11949809 is 90894911.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11075584 + 874225 = 3328^2 + 935^2 .

It is a cyclic number.

It is not a de Polignac number, because 11949809 - 2¹⁶ = 11884273 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (11949869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5974904 + 5974905.

It is an arithmetic number, because the mean of its divisors is an integer number (5974905).

Almost surely, 2^11949809 is an apocalyptic number.

It is an amenable number.

11949809 is a deficient number, since it is larger than the sum of its proper divisors (1).

11949809 is an equidigital number, since it uses as much as digits as its factorization.

11949809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 41.

The square root of 11949809 is about 3456.8495772885. The cubic root of 11949809 is about 228.6232116121.

The spelling of 11949809 in words is "eleven million, nine hundred forty-nine thousand, eight hundred nine".