11781009 has 12 divisors (see below), whose sum is σ = 17059536. Its totient is φ = 7834392.

The previous prime is 11781001. The next prime is 11781013. The reversal of 11781009 is 90018711.

11781009 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11781009 - 2³ = 11781001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11781001) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2802 + ... + 5604.

It is an arithmetic number, because the mean of its divisors is an integer number (1421628).

Almost surely, 2^11781009 is an apocalyptic number.

It is an amenable number.

11781009 is a deficient number, since it is larger than the sum of its proper divisors (5278527).

11781009 is a wasteful number, since it uses less digits than its factorization.

11781009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3276 (or 3273 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 27.

The square root of 11781009 is about 3432.3474474476. The cubic root of 11781009 is about 227.5416113556.

It can be divided in two parts, 1178 and 1009, that added together give a 7-th power (2187 = 3⁷).

The spelling of 11781009 in words is "eleven million, seven hundred eighty-one thousand, nine".