11781439 has 2 divisors, whose sum is σ = 11781440. Its totient is φ = 11781438.

The previous prime is 11781433. The next prime is 11781461. The reversal of 11781439 is 93418711.

It is a weak prime.

It is an emirp because it is prime and its reverse (93418711) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11781439 - 2⁹ = 11780927 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11781433) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5890719 + 5890720.

It is an arithmetic number, because the mean of its divisors is an integer number (5890720).

Almost surely, 2^11781439 is an apocalyptic number.

11781439 is a deficient number, since it is larger than the sum of its proper divisors (1).

11781439 is an equidigital number, since it uses as much as digits as its factorization.

11781439 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6048, while the sum is 34.

The square root of 11781439 is about 3432.4100862222. The cubic root of 11781439 is about 227.5443797009.

The spelling of 11781439 in words is "eleven million, seven hundred eighty-one thousand, four hundred thirty-nine".